I think it was the smartest move to lessen the learning curve and appeal to a broad audience.
And I think a flat bonus for highground and backstab to increase the %to hit (eventually) + the necessity to learn and play with the deep and interresting DnD advantage/disadvantage mechanic at higher difficulty level was better.
Combats are brainless in BG3 if you play the game as intended and nothing will change for higher difficulty levels (except that you'll have to learn not to use true strike and so on anymore )
You're fan of jump/disengage but want it not to be a disengage anymore. Okay.