We could totally get a second TF2 server running, we'd have the numbers. Normally need to queue for a couple of minutes for a slot in the evening, which does rather suggest it's a popular server. The server was down today and while playing on random pubs I spotted at least half a dozen names I recognised from the PCG server. It's a sizeable group.
If you do get a second running, maybe even consider running a different rotation on it? While the current rotation isn't bad, I do feel the novelty value of the new maps is starting to wear out slightly
I'd be up for some other CP maps to pop up in the rotation, at least from time to time. A different rotation also gives the second server something unique instead of just being an overspill of the first one.