[rdonj]

There are ways to make your mages stronger, such as with items (made with construction) and by empowering them (usually a last resort). Also you can sometimes summon mages that are more powerful, though usually to do this requires booster items to enable your mages to cast the summoning spell. Also, in battle you can make communions of your mages if you have astral magic, which make your mages stronger in that battle. There is also a blood magic communion and there are also items that can allow commanders to act as communion members even if they don't have astral. You can even give your mages gems to allow them to cast spells higher than you could normally cast (i.e., nature 2 mage with 1n gem could cast a nature 3 spell). I always forget that one myself.

So the short answer would be no, you're generally capable of getting 2 or more levels higher in a path than your mages can cast natively, though it may take some work. Casting spells with really high requirements though can be a pain without having the paths on your god.