Well, since my cats have decided that I am not permitted to sleep tonight...
The concept is good, but the system needs to be radically changed, because as-stands, the general implementation in games is rubbish.
These i'm not really on-board with, for the following reason...
1; Handling Dual Weilding in such a way really restricts what you can do with it, how you can react to different actions, the type of interactions you have available and so forth. It also falls into the weirdly automated combat you get in many games like Arkham and Assassin's Creed use, which is just so unnecessarily limiting.
2; Difficult to do without going full-on Fighter, and even harder to do with a First Person element. Hand to hand does definitely need some work, but trying to make it more kung-fu (which i assume is what you mean by Martial Arts, as there are dozens of unarmed martial arts out there and some are little more than brawling that would actually make Skyrim's boxing seem elegant). As for the dagger thing... well, it depends on the Dagger. There are literally hundreds of different variations on the dagger, some are better at stabbing, others at cutting.
3; Activatable skills on a power bar are a no-go for me, i'm afraid. Mainstay of RPG's or not, they're a rather sloppy and archaic concept that TES has never really used, nor does it need them. A better Favorites menu for Items and Spells, sure, but no quick cast hotkeys or power bars.
4; Virtually impossible to do in First Person. And, frankly, it goes too far into that automated combat that has become endemic in games these days. It takes away the ability to have manual and meaningful control of your actions for the sake of being flashy and in doing so also limits the other variables that can be attacked to actions, weapons and armour.
5; Could be interesting, mechanically, but without a justification for it being in there, i don't think it has a place. A better and more responsive basic combat system would fulfil it's functional role, and be less intrusive.
6; Game Modes are too limiting in their concept. Having a range of toggleable features is a far better approach that allows you to include all the same variables, but also allows players to tailor their gameplay more to their liking.
7; Vampires and Werewolves are exceptionally rare beings in Tamriel. An adventurer, picked at random, would be more likely to be an Imga than a Vampire. Being able to start as one just makes them seem more plentiful than they are, and causes all kinds of problems with the early game.
8; I am against the notion of Alternative Endings and having the game that gives you too many mutually exclusive options to big decisions. If you want to be evil, fine, but the game shouldn't be giving you equal opportunities and attention for basically playing it wrong. You do that at your own risk, and face the consequences of that decision.
These i agree with, with a few caveats.
Disguise and overall presence is something which can be determined and influenced by several things, from what you're wearing to certain stats, to local status, and have them essentially impact the distance at which you are identified. Making it TOO simple could make it easily abused, but making it too complex would make it impossible to understand and unnecessarily convoluted, so it's something that needs to be somewhat carefully considered.
Timed quests, similarly, are a good concept which can be problematic if not managed properly. Attaching time limits to actual quests is problematic, but it's a good regulatory tool to manage Radiant Quests.
I generally agree about customization... I think games like Black Desert and EVE Online set the standard for what we should expect (even if we aren't likely to get it) from character creation in games. Chronicles of Elyria is looking interesting as well, but i've seen very few actual videos showing their character creation and can't really pass judgement yet...
In terms of the overall designs in Skyrim, however, i think i disagree. I thought they were the best in the series by a very wide margin, particularly after the absolute abominations of Oblivion. The angularity and exaggerated cheekbones made them look haunting and regal at the same time, and they embodied what an Elf should be; not some overly pretty super model, but a terrifying and grotesque beauty that was visibly inhuman, but hit enough of those elements of attractiveness that they were hard not to admire. They DID suffer from the fact that everyone in Skyrim was filthy and looked like they hadn't slept in a week, but i much preferred their design over previous iterations.