Veteran D&D player here, and veteran BG 1/2 player, but not a D:OS player.
1. Mage hand: Mage hand is definitely overpowered.
2. Too many surfaces: There's simply way too many. Surfaces shouldn't be a thing cantrips make, or if the cantrip makes a surface, that's all it should do. I could see using firebolt as an attack spell or to target the floor, getting variety (I'd totally let a player do that in my games if their target was standing among something flammable). Every large fight having archers already on high positions with multiple alchemist fires or acid flasks is a huge drag. The abundance of ranged attackers and their tendency to go for the back line is difficult for balance too.
3. I'm assuming you're talking about the enemy rangers here? I didn't mind this too much, but I think it would be better if the animal companions were there at the start of combat and not summoned right into the midst.
4. I've long used advanced humanoid enemies. Bog standard enemies out of the book get boring after a while. I cut my teeth on 3E, so the idea of NPC classes (adept for spellcasters, warrior for combatants) makes perfect sense for me. They create dynamic fights. The PCs are special, they don't have to be the only Wizard in the world to be special.
5. Action economy. Disengage and Hide need to be actions, you're very right about that. I'm okay with jump being a bonus action, but it shouldn't come prepackaged with disengage. It's too easy to jump around the battlefield. That should be a rogue's thing. Also, did you notice that they didn't give the Thief Rogue their +Dex to jump distance bonus? I was really looking forward to that on my Rogue. (On rogues, not being able to proc sneak attack on my off-hand attack really nerfs melee rogues. Being able to apply poison as a bonus action automatically, and not just as a Thief Rogue ability with Fast Hands, is potentially broken).
And I fully agree; there's too many archers in every fight.
I'll add my own; I don't like that food heals HP.
