Definitely 3. We could use a multi-biome planet and the fire-and-ice theme fits the lightsabers of Finn/Rey and Kylo. I also like the idea that the Starkiller Base planet is Dantooine.
I like both of those ideas too, but you can’t really have the main base of the villains be the fire-and-ice world and Dantooine at the same time. U kinda have to pick one or the other. I think Dantooine serves better as some kind of base for the heroes, actually.