Well maps for gather, are afaik generated by kaggen. That means it's absolutely random. Well essentially kaggen generates three basic types of maps, kinda A-shaped, V-shaped, and flat. Obviously the V-shaped maps are the most stalemate inducing ones, simply because every team has the high ground when defending, which is very beneficial in KAG combat. And, vice versa, A-shaped maps are the very unbalanced ones, on which a match ends in 3-6 minutes (because the team that gets the hill basically already won). Well so one could think that flat maps are the perfect golden ratio... But it doesn't work. Maps that are flat are often causing stalemate too, or are just plain boring. And that my friends is why we need the glorious race of mapmakers, people with human, abstractively thinking brilliant minds, who can predict what an element they add to the map will cause. And use them so that the map is both fun to play and balanced.