I'd say medium armor should return again, while this wouldn't necessarily add more srmor as Bethesda can still just put those armors trhat would be medium if the skill existed into light or heavy instead, depending on which catagory they lean towards, but returning medium armor would allow more customization in terms of what armor you wear. You could have light, less weight, more mobility, but less defense. Heavy, very strong defense, but much more encumbering, or something in between, in Oblivion, the light and heavy options are covered, but nothing for those who would prefer to have better defense than light armor without turning them into walking bricks, still, if Bethesda doesn't want to do medium armor in order to keep the amount of skills in the game at one that is easier to balance, I can understand that. But the lack of unarmored is harder to justify. Traditionally in RPGs mages are usually supposed to wear robes and not armor, and while I'm glad that the Elder Scrolls gives the player the choice to defy this stereotype, it should still give you the option to adhere to it if you so choose, not to mention other character types might not want to wear armor. In Morrowind, Bethesda at least tried to give us the option to wear no armor, the skill was broken and would not function properly without wearing at least one piece of armor, of course, but that's a flaw in game programming which can be avoided in a new game. And if you dealt with it, whether using one of the "unarmored bug workaround" type mods, just wearing one piece of armor, or using the Morrowind Code Patch to properly fix it, unarmored characters would still be underpowered compared to armored ones, which was not completely unreasonable, of course if you don't wear armor, you're going to be more vulnerable than one who does. The main real problem in this case was that unarmored characters always had less enchantment slots available than armored ones, which is why I can't agree with those who say the ability to wear armor over top of clothing should return. But still, Bethesda tried, they didn't even bother in Oblivion. Sure, since armored characters can't wear clothes with their armor, they don't get more enchantment slots than unarmored characters, or they wouldn't, in theory, if unarmored gloves still existed, and that's assuming that you're wearing shirts and pants, if you wear robes, they take up multiple equipment slots, meaning you can wear fewer items, thus fewer enchantments. But they still get a lot more defense, since unarmored players have ABSOLUTELY NO WAY to be protected at all, without using magic, and while it's true you can use shield spells and enchant your clothing with shield, armored characters can do that too, and get the benefit of defense from both armor and shield. So in the end, not wearing armor is simply not desirable. I don't expect unarmored characters to have as much defense as those wearing even light armor, of course, but I DO expect the game to give us a chance to make them a viable character type, which Oblivion doesn't. It wouldn't even be that much of a problem if unarmored characters could have benefits to make up for their lack of defense, but as it stands, the only benefits to not wearing armor are that clothes are lighter than armor, and if you use light armor, the difference is quite small. In conclusion, Bethesda needs to make unarmored characters viable, or there's really no point in allowing them at all.
Other than that, I'd say that the current basic framework for the armor system is fine, some modifications to ensure better balance would be fine, but I can't find too much to complain about with the basic setup. I would like to see more variety within individual armor types, of course. I'd also like to see armor have more of an impact on stealth, because in Oblivion I felt that the penalty to stealth for wearing heavy armor was not strong enough, and it also bothered me that it became irrelevant after a certain skill perk removed the effect of the weight of your boots on sneaking. Wearing armor should always add some penalty to sneaking, and while this penalty can of course reduce with increasing the appropriate skills,
My opinion is this: Get rid of glass armor, it is the all time worst armor I have ever seen (at least the oblivion version of it). I'm about to date myself as a complete novice, but I've only ever played Oblivion in this series. That glass armor though was a complete and utter abomination. Just the concept of "glass" armor sounds stupid. Call it Glassteel or some kind of "magical" glass but don't call it glass because that defeats the whole purpose of wearing it.
The Elder Scrolls "glass" armor is not made out of window glass, it's a form of volcanic glass that is strong enough to make armor, in Morrowind, you could even see glass mines, which are pretty much what you'd think. I'd also point out that Morrowind's glass armor looked very different from Oblivion, and I'd say it looks better, maybe you'll agree, and maybe you won't, either way, you should probably see how the armor type looked in older games too before complaining about its
very existence in the series.
Now, I might argue that if you don't want people to think that a material behaves like the glass in their windows, you probably shouldn't call it glass, but it's already part of the world now, and the only thing removing it will do is give players one more reason to complain about inconsistency in the setting.
It's gonna be heavy armor and light armor again with a very small chance of including unarmored. All in all medium armor was kind of pointless, I do want lots of variety in the types of armor you can find though.
Medium armor was "kind of pointless" in Morrowind because in theory, it's supposed to be between light armor and heavy armor. Lighter than heavy armor, but more protective than light armor, but it didn't really do the latter very well, while it was certainly lighter than heavy amor, you'd be hard pressed to find medium armor with better defense than glass, but that's a problem with game design, and using that as a justiication for not including it would be the same as saying unarmored should not be included because it was bugged in Morrowind.