This is where I think some of that user-created units streamed through impulse would shine. I mean if you build a few new units, but don't have the time to create a whole race and such, you could throw it into a skirmish battle and BOOM! instant use from units. What more, it would help with battle balancing and such. No having to build through crazy (possibly custom) tech trees to test out anything. No anything else. Just plop in the units. You could have a point mechanic that devised a 'value' for the unit based on the stats and abilities the way magic item creation in MoM worked. So that way you could play a 10,000 point battle or something similar.