On the topic of Ice/Electric and Fire/Water Pokemon, I think I know what they could do with both of those.
I've been thinking about Cryogonal evolving into an Ice/Electric-type, based on thundersnow -- just imagine a Cryogonal with the bottom half shrouded by a dark thundercloud with its tentacles hanging from the cloud. It'd make Cryogonal so much better, and would give it a much wider movepool.
As for a Water/Fire-type, I'm thinking of a squid with a volcano for a head -- kind of based on underwater volcanoes. =P It could learn moves like Scald, Lava Plume, Hydro Pump, Rock Blast, and Octazooka, and then its support moves could be stuff like Smokescreen, Will-O-Wisp, Rock Polish, Wrap, and Haze. It could also have Suction Cups and Aftermath for abilities. Of course, even though it's a Water-type, it couldn't learn any Ice attacks, seeing how it's part-volcano; I mean, that only seems logical, and not every Water-type should have access to Ice attacks. =P