But he can't have weak attributes all over. He needs to be good doing something. He probably has high wits so he will probably be a good candidate for scout and lore skill rolls, perhaps even survival and insight skill rolls. As I said above, he needs to find himself useful.Our mage really struggles to gain enought points to actually cast a spell. He is rather weak and fragile, so he can't really push to die to often, because it will break him. So he rather fail and take the consequences then push and reroll the die.
I would probably add something that allows spellcaster to regain a pool of willpower. To play a mage that can't use any spells really sucks.
The player in my group that plays druid, he got most of his WP from survival skill rolls. Another player in my group plays a halfling rogue. He got a majority of his WP from dodging (move skill). He doesn't like to push his melee skill rolls because he isn't as good in it and strength is more dangerous to get damaged. And, yes, the halfling get WP by dodging, WP that he then can use for his kin talent if he misses his dodge (he is very hard to hit, I must say).
I must add here that we didn't have this flow (regarding WP) in our first couple of sessions but then my players have learned that they must share all the "chores" between them, combat or non-combat chores.