I just played round one of tournament as the Rook.  I was in the beta, but I'm far from a gifted player, so I put it on Easy.  Unfortunately, that is just WAY too easy.  I got a ton of money pretty quick, and fairly soon I had the All-Father's Ring, and--eh, I can't remember the other artifact's name that I got.  It was the one that would give you +20 PERCENT damage for 10 seconds.  After I got those two, it took me about 5 hits to kill any Demigod.  I forgot to look at their levels, but I don't think it should have been that easy.

ANYWAY...  I think it would be really nice to be able to change difficulty settings in between Tournament rounds.