If the player character is voiced in any way I'm writing the series off.
Like you, I was hoping F4 would give us a glimpse of the potentially awesome things to come in ES6, but it was very off putting. It looks somewhat nicer (except the actual character models), but gameplay wise, none of the clunky design has progressed.
I want quality of life improvements in ES6 over anything else.
I want to properly navigate the terrain. It's all hills and mountains and etc, and all we get is a shitty "run in place" animation. We climb by spamming the jump button while we float upwards? Enough of that crap.
I'm not a floating camera. I want a slight and natural head bob as my move. Doom was doing this in 93. ES can too.
Give me a proper camera angle when I speak to people. Enough of this 'locking it wherever the hell you happened to be when the convo triggered' crap. Let me pull up a chair at the bar when talking to the bar keep, or sit down at the camp fire with the hunter and etc... at the very least clear people out of the way and let me make eye contact. No more super important conversations while staring at a book shelf, or my feet, or anything else.
I'm tired of objects I take just disappearing out of the world. I want my hand(s) to reach out and pick it up. Apply this logic to any object interaction. Pull switches, push doors opened, etc... Look at LA Noire for what looting a fallen foe should be like.
Fix the crafting and the inventory systems. I'm tired of having 7000 different types of each potion with inconsistent names. I'm tired of not being able to easily get rid of these things. I'm tired of having left over quest items and books and etc the entire duration of the game. It's a mess. And I'd prefer to keep only what I need and can carry. Less is more! Let me keep some potions in my belt. Ingredients in a pouch. And maybe 5-10 items in a backpack. (Perhaps they start out with 3 slots, and you can craft to 10 over time)
I also shouldn't have to tab out to UESP to find out if a container is safe or not. Tell me in the hud. Let gemstones be used as currency!
I'm tired of looting every inconsequential object in a dungeon. It's a heroic fantasy game. No one fantasizes about surfacing from a dungeon battle with 60 pairs of pants and 700 leather glove sets. Once again, take notes from LA Noire for corpse looting. Let me easily grab the gold pouches and arrows, and leave the option of a detailed comb over for strong enemies and bosses. I'd rather come out with my quest item and a nice item I can keep or sell than combing over every inch like a bum looking for discarded cigarette butts.
For anyone reading that hasn't played LA Noire, you can lean over a body and move it's limbs around, and look in pockets. If you want to loot something, you actually go for it and take it off with an animation. This is much more immersive then a inventory window all the time. And you would only bother on enemies with something worth taking. Maybe the jewelry/weapons/quest items and etc would flash to indicate they were of uncommon quality.
Let me camp, hunt, and fish. Setting up camp for a night and cooking a fresh kill. If I need a pelt off an animal, actually skin the thing, like Red Dead Redemption.
Fix the combat. It's clunky as hell, and completely breaks down when there is more than just the player and one enemy. There isn't a single group combat scenario in skyrim worth a damn because of this. It also makes having a companions very frustrating.
Fix the NPC AI. They talk over each other. They all dog pile on each other. Companions need to help instead of hinder. Stop running AI cycles on NPCs that aren't in my zone, and do better AI on the ones I'm actually interacting with. Let me interact with them more like Fable 2, where they can react good or bad depending on my clothing and hair, reputation, instrument playing, boss head waving, past actions, and etc...
Make the mounts worth owning. Let them have names. Let them carry some items. Let them grow over time. They should be trusted companions. Look at Epona in Ocarina of Time.
TLDR Evolve the game quality wise. Stop releasing the same game with the same problems over and over again with a slightly nicer coat of paint. ES6 has so much potential, and all of it has already been done better in other games.