Ok so far in morrowind we got a lot of weapon that was cool to use and got removed in other tes for unknown reason. For all those weapon, there where a lot of skill that come with (short blade for wakizashi, taito, dagger and of course, short blade), marskman for crossbow, dart and bow, long blade for long blade, katana, dai-katana, greatsword, and surely i miss a few, and finally blunt for axe, staff (do you know you can smash an npc with an unenchanted staff in morrowind? that's cool), club and surely many more (they where a lot actually, i'm not sure if i remember them all), for armor we goth unarmored light armor, medium armor, heavy armor and there where a lot of pieces actually (shoulder, helmet, shoes, robes, shirt, pants, chest, and surely a lot more i miss) and now comes oblivion, helmet, chest, pants, shoes, gauntet, and in skyrim, we got even less armor (do you believe a company that remove stuff from game to game? i mean wat? speaking the fact that skyrim become way too easy at a level (but i won't enter in that).

Now i'm just proposing that we pick everything that was in previous game and make a skill tree. The skill tree could be composed of 4 main skill, Weapon, Defence, Spell casting, crafting and thieft.

The weapon skill could be developped in two handed and one handed, that could be developped in blade and blunt, that could be developped in each type of weapon (katana, dagger, short blade, mace, etc) and to be able to level up the mains skill, you have to level up their children skill, and to be able to max a main skill, you have to max all of his children skill, you can be level 100 in axes, and be lvl 50 in blunt because you didn't leveled mace for example (in that system you wouldn't be able to level up blunt just by using a blunt weapon if you always use just axes, to be able to level up blunt, you have to level up all the weapon that blunt have, the level of the main skill would be the middle of every of his children skill (if you have a level 100 axe, and a level 15 mace skill, your blunt would be level 27), same thing for the skill weapon. That way, people will be forced to change weapon if they want to become stronger (the attack power of an axes could be based on the skill weapon, and all of his children skill and not just the skill "axes").

for Defence, we could have the skills armor and blocking, armor would divide in heavy armor, medium, light and unarmored while blocking could divide with shield and weapon (maybe make a connection with the weapon like, if you're level 100 in the skill axes, you would block a little more than with a club?).

Spell casting could be divided into offence and defence that could be divided in every magic skill we know (conjuration, destruction, restoration, illusion, alteration and mysticism) that could be divided by the effect? and of course, make in sort that every skill level mather in the cost of magicka.

Crafting could be divided in every crafting (cooking, blacksmithing, enchanting and alchemy) that could divide in food, drink (for cooking), weapon, arnor (for bs) , same for enchanting (because you enchant armor and weapon) and potion and poison for alchemy that could be divided in the magic type of potion (same for enchant) and maybe at the extreme, the kind of magic (like fire damage or whatever xD)

And finaly thieft that could be developped into sneaking and stealing, both those skill would have as children skill the skill pickpocket( you need to sneak to pickpocket, and pickpocketing is stealing) but stealing would have stealing (like picking an item on the desktop) and sneaking would have a skill (not sure about the name) but that would mather in sneak attack and being undetected too.

All those skill would give magicka (for spell casting and crafting, except for bs? because bs would be more stamina than anything else), stamina for weapon skill and thieft and finally, health for defence. If you manage to get every main skill level 100, your character will be level 100 (a leveling system that would be based on those skill?, maybe using a formula that will make leveling to go faster at low level and slower at high level?)

And finally, for balance, and god sakes, make all the npc level up with you. The big problem with skyrim is that the ennemy was using weak weapon and weak armor, mostly unenchanted so the moment you where good in crafting, you where like a godlike being (hell i got more challenge with my immortal sheogorath from oblivion with 100% defence against magicka and 103% return damage) cause at least i killed the ennemie slowly even with a daedric mace) than in skyrim in legendary mods where i OS everyone except maybe some few boss, and dragons (wish where too easy anyway). How we can balance that? it'S simple, make ennemie wear armor they can craft. If per example, your character is level 100, got an ubber enchanted at the maximum daedric gear as possible, make the ennemie wear those kind of armor too so we player can get a lot of challenge and fun (yeah, fun) and finally, make in sort that the armor you have on your character will only make the weapon damage be reduced by the number of armor you have and not some silly percentage. Armor is useless in skyrim at a certain point because if you play vs a guy who have a mace that do 1000 damage (it's quite possible in skyrim, especially when you play dual wield) and you have 965 armor, well you just got 15% of the damage wish means 150 (basically, you can get os with that if you'Re a full magicka mage, or a full stamina thieft). now if it was like what i have in mind, i would take only 35 damage.

Now, for all this time eating to be worth it, we need a multiplayer arena. Not an mmorpg, there's just too much bad things in mmorpg (trolls, hack, gold spamming) and i don'T find all of this worth it just for some instance and pvp (we could get rided of instance, i like my tes solo, but with possibility of doing PVP, that's why a multiplayer arena is required, with a way to connect to non official server, like i could host on my computer a pvp instance in an arena, à la Unreal Tournament, where you can connect using the character you leveled in a solo games. so this way, you could test your character in PVP, to see how good he his, or how weak he his.