I'd love the chance to get to play on
the Shattered Plains. That map always looked cool, but the terrain requirements make it difficult to make. Similarly,
Valor's Vale also looks like a unique map to play on. I know that both of these maps are probably a long shot, but I thought I might as well still suggest them.
For something a little bit more conventional, I thought that
Fulcrum was well-designed when I played on it at GenCon, and I wouldn't mind seeing it again.