The limitations of the polygon mesh are the reason terrains are like creating a haunted house. Everyone knows it's made of "illusions" and the best illusions within the framework of the house give the patrons the rush of excitement for a moment that the designer keeps elevated in the patrons by how the path through the house and it's gimmicks are constructed. The better the illusion the better is remembered that moment, so the house and gimmicks have to compliment each other and seem plausable. The terrain is the house and the feilds, ports, strats, etc and any other gimmicks like bridges over streams and hopefully, some of what you can gain acceptance by Hitech are the strawberries on the icing to the illusions created around them.
This is why the smaller the terrain the better from soup to nuts that terrain has to be or it's obvious you are trying to pull it off with strawberries only. And why our competitors may do smaller arenas but, if it's a North Africa arena, the clutter, villages and all the gimmicks are North Africa.
For the most part over the years our Melee arena terrains have been kludge themes and while being so gigantic with so many players, the size hid the kludgeyness. And the terrain editor was not our current one with the new tiles and slightly smaller polygons. There is still a lot of room to work with the micro terrain areas in the terrain editor, it's really time consuming because then I have to test each one and tweak them how ever many feilds have GV spawns to them. One 10x10 terrain can have up to 100+ micro terrains for GV combat that would work as arenas for at least one of our competitors. Oceania was an experiment in looking at some GV micro terrain features to see what the terrain editor's limitations are at that scale. Custom objects 1x1 up to 4x4 still have the limitation of laying down level while with hilly country and small mountain ranges you don't often get natural 1x1 flat level areas unless someone sent in a construction team to remove the top of a mountain or hill. I know individual objects are available in the object list and I've laid them down to create neat GV combat spaces but, I get the impression there are dangers to that concerning FPS and minimum spacing requirements that end up being FPS eaters for players.
Ultimately elevations in our game where GVers are concerned, are best showcased to what players want is on Buzzsaw at field A2 the north spawn on top of the large hill overlooking the airfield. They can take down the GV hanger from a safe position never needing air support while everyone on the field is yelling at each other. Then get down onto the field and stick it to the flyboys for hours because today very few players go shutdown the enemy GV's home hangers. 10 players with planes and GVs otherwise cannot stop three Gvers with T34\85 and a wirbel from screwing their airfield all night long. There is quite a lot of room for micro terrain still to be explored with the terrain editor.