I actually did think about that (rimming the terrain with GV bases & maybe a couple ports). Right now as it is, the "rim" consists of a strip of land at sea level, with the actual barrier behind it that is an almost sheer cliff that levels off at 20k. I thought it might be a way to keep players "in play", so for those guys that simply must leave the map, they would have to earn it and climb up & over.