The flatness is actually just the area in the screenshot. That's the Rebel/CIS cp. Between the two cp's there are small hills and ditches. Somewhat bumpy, but not mountainous. Just enough to prevent you from sniping across the length of the entire map. The "walls" are mainly due to my inefficiency at making boundaries. I'll try to master those in time for the next version.
The units are somewhat explained in the ReadMe. One day, I was on an RPG server with a few friends. I asked if any of them would like a few custom units put in. Some, like Fallen, asked for a unit with their name; some asked for units that resembled characters in the RPG. Talben, for instance, was a Jedi-turned-dark-force-adept. Cat, who invented him, asked for an Obi-wan with a pistol, no reskin. And that's what I did, considering that I'm new to modding and horrible at skinning. I made the skins on the Captain Rex and Night Operator models, so that's the level of my skill at the moment. The units and skins are also somewhat explained in a few of the custom tips I put in.
As for the "really good character", why not? Like Eggman said, munging isn't too hard; and I'd welcome any new unit to help me fill up the sides.
Pics coming soon, gotta upload them.
EDIT - Hooray! Pic time!
If you want more, just ask.