Having less to choose from is good since you wouldn't need 9 type of units for every combat but 3. Then you can plan with the 3 for land and 3 for space (example). Battlegrounds had Troopers, Mech, artillery vehicles, aircraft, boating. All I needed most of the time was AT-AA and AT-ATs. Maybe some troopers for those annoying bugs attackin my AT-AT. Having more would just distract me from my objective. Cant forget about Long Range artillery for those fortresses and turrets Attackign with mass units, have a plan