I fly for CHQ out of Boston and most trips are 3-4 days. I haven't looked at other base pairings recently but BOS, LGA, and PHL will have more overnights than CMH or RIC. Not sure whats happening in STL.
PSA has its ups and downs as far as schedules go. DAY has the most with 40 some lines and no researves (i think). PIT had alot last month but only abut 23 or so this month. Still there's maybe one or two guys scheduled for researve in PIT this month. Not sure about TYS, CVG or CAK. My line this month is blocked to 96 hours with 14 days off. More senoir lines have around 16 to 17 days off depending on base. Usually you have 3 or 4 day trips followed by 3 or 4 days off. It all just depends. There's alot of diffrent lines each month.