The first page loaded quite fast for me. Ditto with the gallery -- of course, it's not instantaneous, but it's only a few seconds -- at least on my connection which is pretty fast (Comcast cable if that means anything to you). Images are always going to take time to load, but you could maybe try smush it ? I've not used it but heard various mentions of it being good. But do make sure it won't conflict with Super Cache. Speed is also one of those things that can be affected by so many different variables - so it's not always easy to fix/improve.
Given your content and audience, I think the colors/design are quite good.