Generally speaking, those systems look like pretty simple and reasonable ideas.
The various systems about chest-bashing would need to be explained to the end-user, though, as the nuances would not be particularly obvious. It's probably a little too complicated for an one-off in-game tutorial, but keeping that information in a tutorials section of the log might work.
I do not like the idea of tying additional positive effects to Intelligence, though. Especially in a system in which without Memory, once again Mages have less need to split attributes away from their primary attribute than other class archtypes. It's also a strange idea to have INT affect items, as mages are much less reliant on items than physical attackers.
