I'm still figuring out the kinks in Forge, but I've been working on two different ideas.
My first map, "Combine 115" is a remake of Black Ops 3's "Combine" map. Since the two games share similar movement systems, I figured that it would play pretty well:
To make up for the lack of wall-running, I added a platform on the cliff side of the map, and added grav lifts to the walls in the center of the map between the two bases (for an exposed but advantageous quick trip to the enemy base). I meant for the map to be a 5v5 objective map, but I imagine that it might play really well as a SWAT map (given Call of Duty's quick TTK).
I hope it can end up being a fun Breakout map as well, though I haven't quite set it up for that yet.
Edit: I have actually playtested it. This clip gives a pretty good idea of how it plays, but I've since added a number of requested changes: