1) Separate the weapon skills again! I don't see why Axes have to be merged with Blunt, for example. Long Swords and Short Blades I can sort of see, but even then I'd like to see them made separate. If the issue is that they're not distinct enough and short swords are all one handed while long swords can be one and two handed, then maybe allow Short Swords to be dual wielded, wink wink nudge nudge. Also, bring back Spears. These also have the potential issue of being "underpowered" if we only have two handed spears and not one handed versions, so maybe give us a one handed Trident or something.
2) Along the same lines as above, bring back Medium Armor. Admittedly I think I understand while this was removed and it
is an issue, Medium Armor doesn't really have anything that sets it appart. Heavy armor offers more protection at the cost of weight and possibly fatigue, light armor offers less protection but also weighs less and would possibly provide less of a penalty to fatigue costs (I can't remember if armor type affects fatigue usage). Medium Armor is pretty much right between them, which honestly is pretty boring.
Maybe provide weaknesses/strengths against different damage types based on armor type. Maybe Heavy/Plate armor could be weak against blunt damage and strong against thrust/piercing. Medium Armor might be weak to thrust/piercing but strong against, say, Slashing. Then Light could be weak against slashing but strong against blunt. What is weak and strong to what can be argued (Medium and Light especially could probably go multiple ways), but something to make the different armor types (especially Medium) more distinct from eachother. Doesn't have to be much, just enough to "justify" having Medium Armor added
3) More rewards for exploring. This could be anything from new, interesting scenery/surroundings, a unique book or note or something that can only be found in that spot, hard to find locations that are mentioned in existing stories/tales/books and such, and, of course, unique loot. Everything doesn't have to "reward" the player with an increase in character power, just give the player something that makes them
want to explore the world, outside of exploring it just for the sake of something to do. Morrowind was great in this regard, I think it's unfortunate that this was lost to a degree in Oblivion.
4) Scaling shouldn't be used as a blanket across the bored "fix." I think I understand why this was added, it can be a huge letdown to encounter someone that's obviously supposed to be a Big Baddie then wipe the floor with him in a single swing, and it can also be frustrating for someone to be out exploring then get slaughtered by a random hostile NPC. However, it's also frustrating for every random bandit you encounter to be your match. If you want to scale UP certain "important" NPCs then I'm all for it, and if you want to scale DOWN certain enemies that aren't meant to really be a big deal then I can also understand that. The enemies that are meant to be truly challenging should, ideally, remain challenging regardless of how much you've trained (in the case of someone that's obviously meant to be a big deal, I think it's ok if these guys don't scale down and can slaughter someone that attempts to fight them before they should). Your random encounters, however, shouldn't be challenging a level 30+ fully pimped out hero of the universe.
5) NPCs that offer quests or give some kind of lore/story snippet getting themselves killed. I do enjoy the fact that NPCs in general can wander around hunting or whatever and get their dumb selves killed, I think it helps add some some nice realism to the world. But can we please limit this sort of thing to generic NPCs that won't be missed? It's so frustrating to be locked out of something because an NPC got himself killed before I got around to accepting their quest. Now in the case of an event where you might encounter an NPC being attacked and saving him allows you to get the quest he offers, that I feel is a good exception to the "quest NPC got killed" issue. It's mainly the issue of these NPCs getting themselves killed when I really have no way of preventing it.
6) Flying. Come oooooooooooooooooooooooooooooooooooooooooooooooooon