Hi Lance, Good Day Mate....
How's the Summer going down under?
I agree with your comments, and you might want to add them to the feature suggestions forum.
I sure that in the future you'll have a variety of choices for painting the terrain. You can change the rock and paved rock textures now. I think the method is in the FAQs, but in the future it should be much easier with many more choices.
I'm with you on grouping. Would be particularly helpful is you wish to move the entities as a group during game play. Might also improve FPS. Doing so is a big job, but we'll see.
As for map size, I'm very happy with the 51,000 x 51,000 unit main map. You're not limited to the size of your construction, so it can be as small as you like, but the larger map (as a background) adds great scope. I don't think reducing the size of the map will improve FPS as most of the map that is not in visual range is ignored. If your in a purely interior mode I'm told you can turn-off the terrain, but I have not yet tried it myself.
Good Luck
"There is no spoon"