Um...yay...it's a load of caulk...
The Mon Calamari design looks like it could be promising. However, there are a couple things you ought to watch out for. First, the terrain itself could look much more smooth and sexy...check out rgoer's notes on the subject of terrains (
http://www.lucasforums.com/showthread.php?s=&threadid=106198). Next, that's just one big box...so you may have VIS issues. I hope the terrain brushes aren't structural...but in any case, you should work out some system to split up the map into separate leaf nodes.
For your skybox, I myself wrote a tutorial in the subject (
http://wso.williams.edu/~jshoer/terragen.htm), so you'll be able to take care of that yourself.
Is there going to be anything in these maps besides terrain? Also, maybe some more varied terrain is in order...right now, Dathomir and Mon Calamari look exactly the same except that Mon Cal has a much higher water level.
Ditto on the comments about having one WIP thread. The problem about splitting it up is that now people know you're making a couple planets, but we have no idea what your mod is any more.