Not sure why this map gives you so many issues, but it's a rather lousy assumption to say everyone has the issues you do with it in terms of performance. It runs for me just fine, and any map in Guns has the potential to give problems on the hardware front. I'd be open to that argument only for 4v4's currently.
Call me crazy, but rushing the point on a KOTH is pretty standard. Even did it in a galleon to win (Flotsam). With competitive teams, they will get there before anyone caps the point for themselves, so you start with an initial engage to determine who holds first. Then it's up to the loser to coordinate their counter. While I can give you the point that takes a long time to cap once its already been captured, its not impossible if you keep your momentum and don't blindly rush in one at a time.
All of that, while happening over a contested point, is much more entertaining (and less time consuming) then taking pot shots from spawns.