I feel the same during my bandit playthrough, and I thought raising my dexterity stat would also increase the strength of my katars. Unfortunately, that’s not the case compared to two other classes where raising one stat that represents their greatest strength would increase the weapon’s stat as well. For Bandits, It comes to the point that I have to upgrade 2 stats per level, instead of my other playthrough where I spend 3 points on one stat for a couple of levels.
I won’t lie, playing as Bandit has to be my favorite class, second being Fighter. I think what’s underwhelming is that there’s not that many strong katars aside from one that’s dropped from the Medium difficulty Dungeon boss. I also felt the same when playing as Mythic since it’s hard for me to collect better weapons that’s not the Diva Staff.