It's an original design. I'm eager to see how it plays. The unboxable flag and the tall-topable wall in the middle should make for a higher scoring game. Kinda reminds me of that map on the rooftop with the water tower on each side and a smokestack on a wall in the middle... what was that called... anyway it's not that map and that's a good thing.
Sorry for the criticism if this was your final release, but the walls around really do lack. The stripe was a good addition but it needs more- I know you want to keep it simple but decals, windows, anything to break the flat repeating concrete texture.
Only real issue: The no build area around the flag is misleading. There's the yellow/black stripes around the flag where one would think the nofreeze would be- but it actually extends the entire width of the walkway.