As a big fan of the series since Morrowind, Skyrim is probably my favourite. That said, there are still things to improve. Here are some of my ideas:
- Keep the main series singleplayer.
- Keep the random quests/events, but add more diversity to them.
- Bring the arena back. It could actually be a (the only) cool way to add multiplayer, without killing the franchise.
- In the arena, you should not only fight, but also be able to be part of the audience, bet, etc...
Map and journal:
- Make the map more interactive. I visited an interesting dungeon, so why not the ability to write a note and add it to the dungeon icon in the map?
- Stores and other important places in towns, should have their own icons.
- The description of miscellaneous quests should be more elaborated. After hundreds of hours accepting quests in Skyrim, i never remember who asked me to do this, or why do i need to visit that place. There are hundreds of quests in the game, so there should be a more complex journal.
- Some dungeons, for example, a cript that has been closed for centuries, should't have lighted torches. Make them darker and more scary.
- Dungeons without torches, or daylight from the exterior, should be completly dark, forcing you to use a torch or magelight. You should also be able to light torches with fire magic.
- Traps should actually make damage.
Loot and exploration:
- Gold should be harder to find. I explore alot in theses games, so i always end up with lots of gold and no use for it.
- Enchanted items, artifacts, etc, should be alot more rare.
- Once in a while, sacks should have more than apples or carrots. Make important loot rare, sure, but still unpredictable.
- Night should be darker, more scary and incredibly more dangerous, to the point you feel the need to go through the roads or pay to spend the night in an inn. To make that possible, some night creatures (wereworves, vampires, ghosts...) should be more active, unpredictable and powerful at night.
- Some rare items or properties, should be incredibly expensive. Only possible to be brought, after like 150 or 200 hours playing the game.
- Lockpicking is too easy. I usualy open master locks just for fun, and lose 2 or 3 lockpicks at most. Oblivion's system was a better challenge.
Combat and Magic:
- Arrows should be affected by physics, like in Oblivion (the longer the distance, the upper you need to aim).
- Some enemies should also have mounts.
- Fast travel could be replaced by a spell. You could only travel through the entire map, later in the game, at the highest levels.
- Followers (and NPCs in general) should have visible characteristics: Attack, armour, magic, stamina, etc, so you could know exactly which gear you should give him/her.
- Most NPCs in Skyrim had the same dramatic tone on their dialog. Give them personality, sense o humor, etc...
- Town guards should be able to give us indications (where's the inn, the general store, etc...), like in Oblivion.
- Make it harder, some places close to impossible until you are a really high level. I started my two Skyrim character in the hardest difficulty, and while it started as a challenge, it turned like a walk in the park too soon.
- Add a hardcore mode (no fast travel, need to eat, need to sleep, etc...).
- Make the game next gen only, and multiplatform (PC, PS4 and X1). Don't go exclusive with a platform your fans may not own.
- No more loadings between interiors and exteriors. You should be able to see the interior of a house, by looking through it's window.
There are more, but i'll post them later. And please, post your ideas aswell.