I'm just finishing act 1 (no spoilers please) and my rampant stealing of everything remotely valuable seems to be paying off in my ability to buy literally anything that catches my eye. I kinda wonder if I'm overdoing it with how much gold I have vs the price of things so far, but I don't want to risk encountering a trader with amazing stuff that I can't afford.
I still have lots of room for even modest gear improvements. eg, not all of my party members even have 2 rings yet, let alone gear that is genuinely useful to their play style. And some of my characters have some gear that are very niche usage that I'm keeping an eye out for something that will give them an edge in combat.