I am a 20 year D&D vet and have probably over 10,000 hours in 5e alone as a DM and a player.
I do not expect Baldur's Gate 3 to be a direct copy paste of the 5e ruleset, and would be shocked if it was. That said, I'm pretty happy with how things are currently. I disagree with OP, because combat does in fact feel like D&D to me. Where it doesn't feel like D&D, I feel it is improved, such as heavier emphasis on environment (much like Original Sin 2).
The action economy is pretty well done in my opinion. I fully expect, and am unsurprised to see that some abilities and spells are not direct translations: jumping to disengage being the one that sticks out most firmly in my head. This is a bonus action in Baldur's Gate 3 and a full action by default in 5e. It depowers rogue a fraction of a percent, and empowers all other classes a bit, but I don't believe that it actually changes very much overall. Especially when you consider that rogues get 2 bonus actions as they develop, which is massive.
Keep up the direction you're going in. But also add the toolset, DM client, and ability to host over 50 players at a time please.
Maybe include a real time with pause option for DMs.