The DDOS attacks are our main issue atm to ensure stability. The majority of good pools is facing continued attacks. f2pool just came back and it's already gone again. Antpool still seems to be rejecting new connections and GHash, NiceHash and Slush are currently stable for us.
The downside to BAN is they are slow to pay... but do come through.
Slow payments is something we can't really have. There is already so much variance affecting our mining operation that the last thing we need is another headache.
The ideal solution for us would be for Antpool and f2pool to get on top of the issues they are encountering so that we can let BigMama sit there and do her job like we did in the first 2 weeks since the farm has come online. Those two pools are the best performing for us with the lowest latency due to their geographic location.
EDIT: Maybe try Block 3 on Mining Rig Rentals (MRR). I find MRR is much faster to rent rigs than Betarigs. You can list 5 pools as back up on MRR and its a simple click to switch a pool from say 3rd priority to first priority. I generally have BAN or WestHash as the first backup pool. Lately, its been only BAN as my first back up tho as its paying better than even West.NiceHash.
We'll be looking into renting out some of our power again since renting power is part of the original manifest of GHfarm.