Whew!  Just finished an hour long struggle against bots on this map.  It was really a lot of fun,  4 out of 5 stars.  When planets are finally given a bigger role (like in v4 or something) you might want to update the map as that planet at the center could make a really nice chokepoint, maybe give it a little nebula cover, though more asteroids could restrict movement, changing the "openness" feel of the map.  And as for being your first map, I'd say you're off to a really good start!  Keep up the good work.