Game mechanics: This game should have combat in real time, like ALL other RPG games have including this very series. Imagine they announce Elder scrolls 6 beeing turnbase, like WHAT? There should be combat action in an RPG, not this over the top tactical gamestyle, at least let us choose which to use like other games ( like Dragon age). It worked for DOS1 and 2, but doesnt feel at home here. In DOS2 you also could do alot more each turn, I remember I could take two turns even, and get extra actions on killing stuff.
Camera: Camera is very bad. I cant look around freely?? I imagine Larian getting alot of feedback on this in DOS2, and they have done nothing to it. In DOS2 there was not so much verticality as BG3 so it was not as bad maybe. I want to also be able to play my character with movement control, not just this click and point thing.
Classes: I get that this game follows D&D5 rules, but seriously. take the warrior for instance. All he can do is run up and hit each turn. My warrior is Eldrich knight, congrats you are now a bad mage aswell as you can hit with your sword. Why doesnt it give you warrior-like spells? Like self buffing, magic weapon or something? And where are the warrior abilities? What about charge, jumping strike, whirlwind, stomp, pummel, taunt, shouts, are there nothing in this d&d5 rule? It sucks compared to most other games including DOS warriors, (Maybe this is something you get with Battlemaster?) The mage and cleric has tons of different spells to use, while the warrior can move up and hit once, unless ofcourse you want to be a mage (eldrich knight) instead and cast spells rather than hit.
In my opinion Larian should look more to Dragon age Origins and Inquisition for game design and gameplay. Origins for the combat and Inquisition for the movement control, immersion and exploring the world.
Alteast this early access makes me want to replay Dragon Age Origins..
The answer to most of your questions is already in your own comment honestlly, "because it's a D&D 5e ruleset game".