Many problems come from TB mode. The others come from Larian design of combat (always outnumbering and outleveling you).
DOS 2 was much worse, believe me.
Turn based games should only feature difficult fights, IMHO
It really should not by sacrificing immersion, which is why im i even playing CRPG in the first place. Even DOS2 had a few trash mob encounters where you can quickly score a victory - it makes the game have contrast and make the eventual hard encounters stand out and more interesting.
Otherwise it gets boring and predictable fast.