I led a class on resin crafts when I was a librarian last year. We used UV-hardening resin for faster results, but I think there are more options with 2-part epoxy resin like it seems you used. UV resins also faster layering, though. For example, pour a base layer of clear, then add glitter, then a dyed layer, more glitter, and a clear top coat for added dimensionality without the cure time wait. It requires UV lamps, though, and can smell bad.