Understand that commuting to Sun Country is its own special type of impossible. While you might be used to a Florida to MSP commute with Compass, understand that due to the type of flying Sun Country does that the trips are not commutable in the same way another airline is. Much of the schedule leaves MSP early (6-8 AM) and returns very late (12PM-AM).
I know this has been said many times in this thread before, but with most airlines there is an improvement that happens with your schedule over time. Don't expect that to happen... Unless you are doing day turns (very senior 5+ year FOs, 25+ CAs).
Perhaps the 737 is blinding, but really everyone is try to warn people against commuting here for a reason.
Ask your questions here. We'll answer. Better that everyone else looking gets a glance inside as well if they are trying to make a decision to apply at Sun Country. This airline is a different animal and it is hard to get a grasp of what it is from the outside looking in. The flying and the schedules are quite unlike anything else.