The mechanics in this game do not suck. Maybe work on your character builds? Yeah, RNG can be frustrating sometimes, that's the nature of the R in RNG, right? There are ways to make the numbers work in your favor.

I hate being the git gud guy, but seriously, have you tried multiclassing? Don't use Dex save spells on mobs with high Dex?

I've had bouts of frustration but NOTHING that would make me come on here and whine about the mechanics. The game is too easy, IMHO.