Do you change or cancel many of your flights? If so, Southwest wins even with no FF benefits at all. Does another airline offer better schedule and on-time performance? If so, they win. FF program benefits are far down the scale IMHO, only coming into play when all else is roughly equal.
I take the first flight out on Monday AM, so on-time performance is pretty equal across the board. I've only needed to change one flight over the past 4 months, so that is not a major issue. It looks like a lot of the legacies have pretty comparable programs as far as mile redemption goes; I've never tried to book reward travel with them, so I'm unfamiliar with the blackout/restrictions that are unique to each one.
Also, thanks for moving my post to a more appropriate area. I'm still learning the FT ropes.