1. Add Minigames to Combat
Those who are familiar with the God of War series will know what I mean. Basically, this is a combat enhancer that will go to 3rd person view and use animated sequences of combat where you have to react by hitting certain buttons at certain points to complete breathtaking maneuvers you otherwise would not be able to do. Adds to realism, immersion and cool factor.
2. Make Dialog Choices Matter
Look at games like L.A. Noire that have taken dialog selection to a new level. Not in all cases, but in places where the narrative can fork in different directions depending on your choices, allow the player to succeed or fail depending on their responses. Succeeding may involve choosing many paths through the dialog with no single choice of failure, but makes the player think carefully about the expected response.
3. Destructible Environments
If I want to chop down a tree, let me! Other things include shooting fireballs at wooden scaffolds and having them fall apart. If that means you are blocked from a path. So be it!
4. Add Faction Reputations
As from Fallout New Vegas.
5. Better lip sync and walking animation
L.A. Noire sets the new standard for this. Everything else seems 10 years dated in comparison. When I see mobs walking down stairs using the same animation as walking on a road, it looks ridiculous.
6. Why does my quiver have to float off my back by 10 inches?
This is extremely annoying. Bad enough I can't view my character portrait, but when I gander at my arrow quiver on my back from the side, it literally floats in the air...
7. Rewards/Loot Should Scale
Ok, I like the direction skyrim took on monster scaling vs. Oblivion. But when I am getting rewards for cleaning bandit camps like (100gp) or a weapon that is worse than what I have, its disheartening. There should be a treasure generation system that takes into count what you already have. If I can't find or get improvements to my gear, half the game is lost for me.
8. Better Lighting
This has been mentioned before. The whole dungeon "faux lighting" is kind of cheesy. Yes, I know being in the dark is worse, but there has to be a better way.
9. More Better Voice overs
I'm getting a little bored of every NPC sounding like Arnold. Accents are a nice addition, but am I stuck in Austria? Also, when my character gets hit, all he says is "Ahhhhhh!" Doesn't matter if its a tiny spider or a dragon.....just "Ahhhhhh!" Some other kinds of grunts and umphs would be appropriate.
10. Talking Characters
This may be a divided issue, but I would like to hear my characters voice in conversations. The mute character style is boring to me. Bioware changed over from it in Mass Effect. Hearing your voice is better.
Byes!!

