Likes: Mountains, Tundra Turn-offs: Serpents, Marsh
... speaking of, this makes me think that a Dragon variant of Wings of War might be worth cobbling together.
I think that's the right starting point, with troops being placed on the map (maybe with some ability to move during the game but not much) to be interacted with. Boarding parties/riders could be on the dragons and fight when the dragons overlap or something.
But I don't think there's much out there like this currently...