I decided to be an idiot and do the language of the culture that uses speech, and very precise speech at that, as a locus for magic, so every decision I make tends to go 'well do they /really/ need that many phonemes/cases/tenses/etc - yes I guess they do'. Simple isn't really an option here, culturally. >.> Next language is going to be (C)V all the way.

That aside, this is the kind of thing I'm wondering about. Why a stop or a nasal at the end? Why not allow the fricatives and so forth? Was that just a decision you came up with out of thin air, or did you look at some Earth language to do it?