OnCall, Compensation -- Debate

Here's the situation - 133 bed acute care hospital with 3 MDs (Anesthesiologists) and 9 CRNAs, 5 rooms. Little in the way of complicated care -- no cranis, no open hearts, no high risk OB. We have first call, second call, weekend call. Base, hourly compensation at $52 - $55 -- guaranteed 40 hours a week (whether worked or not), time and a half for overtime, flat call fee with regular hourly rate (time and a half if overtime) plus an hourly call fee added. My question -- what are the different arrangements that are out there? What is fair in terms of the call arrangements? We are located on the East Coast. I need to get an understanding of what drives the hours and arrangements that have been put in place and why there are so many variations, I don't quite understand the rationale. Anyone have a great hospital based CRNA program that's working well and everyone is happy? Thanks in advance.