Whatever Chemist does it'll be a Caster. Surecast/Swiftcast don't really make sense without that factor.

As far as job mechanics go, one of the things I liked the idea of was casting a spell ahead of time and bottling it for future use. The only issue is I can't exactly tell how best to balance that. It's funnily the same idea I liked for Time Mage, though it was more of a time compression kind of idea.