Also, if I equip a staff that gives an INT boost, shouldn’t the damage I deal go up?
Int raises All Res in D4. You can see what each stat does by hovering over it.
A lot of your combat pain points are solvable with gear in endgame (effects still won’t be flashy tho). Pretty sure D2 early game consisted of chugging mana potions non-stop until you got the Tal Sth rune word for your helmet. Which really isn’t all that different from spamming Basic attacks until you get aspects and talents/skill in D4.
Honestly it sounds like you just wanted Diablo 2 (2023). Nothing wrong with that of course but I don’t quite understand why you wouldn’t play PoE then. That game strikes a good balance between modern and old school while also upholding the more hardcore nature of D2.