Awesome work. First time through I didn't notice the big ? button, so I was a bit confused. Might have been a good idea to pop it up at the start for first time players.
Rerolling the low charge trinkets is a cool solution to the problem of running out of them!
The elemental weaknesses weren't immediately clear even with the tutorial button, as others have pointed out (except for the fire guy, that was pretty obvious :P)