I believe most nagas already have Eschew Materials as a bonus feat, but giving it to these guys explicitly is a good idea. I don't like all of the material components being carried in the hood as the rationale, though. Their hoods are studded with gems, not a bunch of random garbage and live spiders and bat dung. They're classy.
Giving our sample a couple of spells that have gems as material components/foci would be a good idea. Stoneskin, for example.