thanks for the comments guys.
As for the point about sniping, I'm hoping this won't be too much of an issue. There are areas of cover that block sniper lines if you're good. This is the first round of three also, so I've made it nice and open so it's easier for Blu to cap and harder for Red to defend. The next two rounds get progressively narrower, like Dustbowl does - and these are actually more like Sniper Alleys than the first round!
I'd like to get the first round on the servers at the next game night if possible, for testing?