As of version 5.5 there's some money balance issues: the money are abundant and the items are cheap. Not that I complain, mind you. It's just that I bought "the best" (to my liking) equipment already and have over 3k money (or over 4k - don't even look at them anymore) and they're totally meaningless. I want to see the story (since I do like it since the very first game), so I cleared available tower several times until saw all(?) content.
Can't really suggest a solution to this issue - both raising prices or reducing income can be disappointing. The standard "RPG way" is to give access to more powerful (and way more costly) equipment, but this doesn't quite fit into this game as I understand it. Maybe add some overpriced accessories with minimal bonuses that are limited to certain levels in certain bodily areas just to encourage player spend money on them? Development notes on next versions kinda suggest that exact approach, if I'm not wrong.
Anyway, really like it so far and waiting for more!