I am one that will love this. Always wanted to know why we went back to the 1500s when the world was flat
Game mechanics to keep it simple...and to simplify movement for the AI I think. Watch the AI try to navigate a crowded area when it has to move down or up to escape--its very slow. Takes less units to defend a 2d area so it reduces cpu too overall. A little more eye-brain contemplation for players to deal with as well.
Still would like to try it out and see what happens. It amazes me how people find all these things they can change. placement in galaxy forge.