Rather too many people here getting frothy over changes from core 5e rules. Larian do their own version of 5e rules. Elemental surfaces are fun, make the map layout and positioning absolutely crucial, and allow for much more tactical play. Some people get hung up on minute differences from 5e: maybe enjoy the game as it is, if it doesn't work in the game, then critique it in those terms. 5e isn't a bible and it's not useful to be fundamentalist.
The changes make the game worse
The optimum tactical play in this game is to run 4 tiefling wizards spamming magic missiles, because it ignores all the ill conceived changes to targeting they've made, and you have fire resistance to deal with the entire world being on fire all of the time
Or 4 Thieves, or 4 Battlemasters, or Battlemaster (Lae'Zel) + Thief (Astarion) + Ranged Shove Warlock (Wyll) + Disposable slot (Player character). There's plenty of variety in terms of what works to the point that you may as well just be saying "Coordination is the optimal strategy".
