I would like to see less development time spent on ‘origin’ style special player characters and more companions that are not player options. There’s a happy medium somewhere between fully fleshed out possible protagonist party members and generic mercenary characters. Baldur’s Gate was known for having tons of party options and party members with their own goals that could join and leave on their own. Icewind Dale was the series for when you just wanted to play through a campaign without the party personalities.
I think this because I think many players will opt for a custom player character, just my opinion.
Shove/Jump/Disengage as bonus actions feels a bit too strong and it’s even more frustrating when the enemies abuse it as well.
High ground and backstabbing advantage are technically too good. Low ground causing disadvantage and high ground providing advantage is the equivalent of fighting blind at the moment which is overly harsh in my opinion.
Double check the encounter difficulties. Most of the encounters rank as deadly when I checked against the tabletop guidelines.
Oh and bring back the BG paper doll for gear management. I found it clunky pulling up the bags and then having to switch to the character view. More boring but useful magic items like rings of resistance and protection.