All RPGs have very unrealistic inventory systems, because that makes looting more fun. There are popular and loved games that throw storytelling overboard and instead focus on looting and levelling. Players could potentially become upset if the PC can only carry a fraction of what they expect. Its much to risky to start messing with a system that players are used to and generally enjoys.
I don't see how a system that makes changing armor take time would be for the better. Is it fun to change armor before every fight? Does it add a feeling of realism? No, its a needless timesink and it breaks the immersion. An enemy should be beaten by skill and wit primarily, thats where the good gameplay is, good armor will increase the time one has and a good weapon will reduce the time it takes but neither should be a necessity.
Oblivion had very low protection values on some armors, yes, but that doesn't mean that the general approach is bad. I am also unsure how Oblivion handles a 5% damage reduction, if it rounds the damage down then 5% will always be at least one point of protection and that is pretty nice when foes hit softly like in the beginning, later in the game 5% will be moot. To have PC's with no armor get crippled by injuries pretty much only means penalizing pure magic users, as if their lower hitpoint pool and lack of armor isn't enough already. Lasting injuries could generally spice things up if done in moderation, just to make the PC appear to be bruised and in agony. But as soon as those become detrimental they may force the PC to take a boring trip to the nearest town to cure them, and that becomes an annoying hindrance if it happens three times per dungeon delve.

edit:
When it comes to armor and % damage reduction, its easy to be fooled by how the numbers work. The important thing isn't the actual % of protection, but rather the fraction of the damage that gets through. Its the fraction that has a significance on the time a PC can last in combat. Suppose a PC improves his armor with +5%, if he had 0% to begin with he will now take 95% of the damage and that increases his general survival time with 5.2%. On the other hand, if the PC already had 90% damage redcution the survival time will become doubled. Depending on the already existing armor, a flat +5% increase have very different impact.
A designer who thinks that this works linearly will make a flawed non-working armor system since he or she doesn't understand the consequences of any changes in armor values. Some understanding of math is required or it will end badly. The approach should not start with assigning protection values haphazardly, instead it should start with the question "how much extra survival time should this armor provide?" and then one calculates backwards and pick the damage reduction from there.
An armor that increase the survival time with 50% needs a damage reduction of 33%.
An armor that increase the survival time with 100% needs a damage reduction of 50%.
An armor that increase the survival time with 150% needs a damage reduction of 60%.
An armor that increase the survival time with 200% needs a damage reduction of 67%.

So because all RPGs so far have had something it should continue to be like that? I think there should be at least a choice on this matter, the (possible?) hardcoe mode could add weight to all items and make changing armor take time, because the movement reduction of heavy armor could easily be negated by simply taking of the armor and running without it until you are in combat and then put it on again. About if it is "fun" to change armor before every fight: that's not the point at all, the point is that the whole negative effect of heavy armor in Oblivion is non-existent. By adding this, players could be "forced" to have the armor on just in case all the time in the wilds, because you really do not start putting heavy iron cuirasses and greaves on in the middle of a combat. The whole inventory opening in the middle of combat could in my opinion be taken away and said goodbye to, but it adds sort this sort of comfort to know that there is a place you can hide in in the middle of a combat.

About armor and the added time it is supposed to give you in combat: This should really be different from who you are fighting against and what type of armor you are using. Meaning that the different types of attacks, such as blunt, slash and piercing should be in the game too, it just doesn't make any sence that a leather armor protects equally against arrows and slashing attacks from swords.

Now finally to the pure mage thing: the whole idea of running into combat without armor and without protecting one self against damage with warding and shielding spells is just about the most stupid thing a person could do in such a world. The warding and shielding spells should protect in the same way as armor, meaning that injuries would be avoided, I mean let's face it, an unarmored mage is not even supposed to be able to survive the attacks of his enemies without his magic, thus he should use it and let the non-mages use armor and other tricks instead.

But I agree that a percentage system could work, if done in a different way than it was in Oblivion and really thought of this time a bit more, but a more in-deapth system could also be added by locational damage protection and a combination of DT and DR. The possibilities with such a system are nearly endless, there could easily be 60 different types of armor materials that would be unique with a system like that.

No, RPGs need to evovle too. But its evolution so far has lead up to things that a game in the genre is expected to provide, breaking away from those expectations can be a bad move.
A combat system can be made very complex indeed. But I am not entirely convinced that it would help the gameplay. A less complex combat system could work equally good and be just as fun. (And just a small side note on complexity: There is a simple looking game called Dwarven Fortress that has a complexity level that is just beyond mindblowing. It doesn't merely calculate damage like most games, in models it and even takes the physical properties of different tissue layers into account, the math behind everything is extreme. Maybe you would enjoy trying that one out.)
If heavy armor need a penalty of some sort, I would prefer that it made stamina be used up more quickly. This will allow the PC to run and jump when needed, but for a shorter time. It could also make heavy armor fighters more defensive, since frantic attacking consume precious stamina.


Its certainly possible to take different damage types into account, but is it complexity for the sake of it or does it really bring anything exciting to the gameplay? I just don't like the idea of having to swap armor before going into battle all the time. Its just annoying.
I'll leave the mage thing alone since they don't wear real armor, magical protection can work in a myriad of ways.

The comlexity of the system wouldn't have to be visible for the player, they wouldn't have to think about the math to enjoy and understand what armors do in the game.

Complexity brings variety even when the player doesn't know about the complexity And that about swapping armor before going into combat: That is exactly what should be taken away, the current menu system allows you to instantly do it, which means lots of folk do it, ofcourse not those who think it is annoying like you or those who think it is to exploit something in the game, like me.

I would like to suggest a new system for implementation here called "Battle Story" ....

Battle Story would be a Bardic skill that you use after each battle to help you collect data about your previous battles without having to do it yourself, IF YOU WANT TO USE IT, that is ....

What it does:

The game records the last 10 battles you fought (not visually, but informationally, remembering the kind of attacks and weapons that were used against you, and specifically the damage done by each weapon, and how it impacted (bleeding, stunning, staggering, bruising, crushing) your character. You don't need to see that, or know about it, the game records it for the Battle Story. Then, when you meet the Armourer, you can "Relate Your Latest Battle Story" to him or her. They listen to you recount your last few battles, which may start with just a few words ...

"I was just outside of town here, when I was attacked by a Goblin Lord with a large scimitar....." and then after a few moments of elasped time demonstrated by a fade, the NPC says "Ahh, okay, let me help you. You seem to be vulnerable to lunging attacks along your sides because you only use leather there. Most of the attacks you mentioned in the last battle ... seem to indicate ... that you should switch to wearing Chainmail, because the most frequent kind of attack you are experiencing appears to be lunging attacks... why don't you look in my shop and find a good set of chainmail to trade for your leather armour?"

The game could then anolyze your recent battles for a pattern of weakness, and the suggest the best kind of armour to wear for that weakness. Then the Armourer could take on the aspect of being a sort of "Guide" to your health, and thus be able to sell his Armour more like he would really try to sell it, by being a survival coach (think Insurance Salesman)...

All of this happens basically behind the scenes. You walk in, talk the Armourer, recant your story, and he simply recommends the best kind of armour for your character to be wearing at this time based on the kinds of recent battles you've fought, which you basically pretend to recant to him as some epic battle tales that only really take place in your memory and imagination between the fades. Would really add some cool immersion to your character having him recount his own tales and have the game provide some advice on the best armours to use, too.

I don't think it would need to be a new skill at all, it could be an aspect of light and heavy armor skills to anolyze the combat situations. being really skilled in either light or heavy armor would let your PC anolyze it by yourself by simply triggering an option in your journal, telling you exactly what seems to be the problem. That ability however could be added to you only after your light or heavy armor skill would become more than 80, before that you would have to seek the help of the armor sellers in the game world I like the idea, in it's rough basic idea form, could be something great

i wouldnt agree that you could move easily in it, yeah you could move but forget about avoiding fireballs and arrows by jumping around like a chimp on cocaine

and yeah, youd swim like a rock

there definitely needs to be more disadvantages to heavy armor than what weve seen in oblivion

Indeed, I said that slower movement cannot be the only penalty for having heavy armor, partly because it really doesn't slow you down that much in combat situations. It simply should rapidly cosume your stamina, and I do agree on the part of jumping: we shouldn't be able to jump equally high with no armor and heavy armor. The movement speed when it comes to traveling from point A to point B should still be in, but with the right design, you can wing your sowrd and block an enemy just as fast as with no armor at all, that's what I meant