There really are too many expansions for a 1v1 game, but thats why there are 4 start locations!
Try playing some computer players on the map, after they build through the tech tree and start expanding everywhere they can get totally out of hand. They enjoy all those resources immensely, especially the zerg.
I did move the minerals at the bases around a little, they were in... not so good places.
I can't really change the terrain much because:
http://tinypic.com/5ds85j