Yeah, I know DTV already pays too well and this thread will be ignored. But still, I'll leave this suggestion here in case someone in dev crew thinks its good idea. I'll keep it simple:
If there is more than 15 players on DTV server, every round whole team survives 33% bonus will be added on final rewards (both XP and gold). Which means, if somehow whole team survives three waves in a row which is highly unlikely, rewards will be doubled.