A priest with a stave, though classic, is also used in all games known to man. The Blazing Priest strives to sway from that stereotype, and wield different weapons. The hammer also gives him some melee leverage, as this class is a short-range healer and damage dealer.
I would think someone on such a holy quest would not care about stereotypes, if that's what your suggest XD. If your suggesting that the blazing priest thought "gee all spellcasters use staffs, I should totally use a hammer, so I can bash the evil's brains in, even though that's against what I stand for(which from your description sounds like burning evil and healing good)
not that I personally mind it, but if you do give him a hammer, it is much like a paladin, as a paladin is a melee/spellcaster pretty much, but in this case you say he has melee leverage but shouldn't ever exclusively use the hammer, which separates paladin from your class. Also paladins can typically wear better gear then your average cleric. I like the idea, and it gives me an idea; elemental weapon types. You obviously have no concern with giving certain people certain weapons, so you could make it where each class can use certain element(s), and even more, make it so they can only use certain weapon types, I.e your blazing priest dude could use hammers, staves, and, uhm, orbs(w.e that is, sounds interesting) of elements light, fire, and some sort of combination of those, like firelight(like fireflys, you could say that they are in the orbs and make orb-exclusive elements with that). I'm not suggesting to put this in your map really, I'm just using it as an example. Idealism is a hobby.
gee kinda rambled on right there..anyways been watching this map since it was first put in a thread.....can't wait to say the least
edit: just reread your description, like the way you put fire and light, maybe instead of firelight(which is pretty cheesy) put brightness
again not suggesting this for your map, just doing my hobby