I like DEN, it's a GREAT airport with lots of ammenities (don't really have a choice when flying F9, almost everything goes through DEN from MKE/MSN!). You can take the train to another terminal without exiting security for lots of food choices! B has the most options IMO, but the Denver Chop House is pretty good in A. They take care of snow pretty well, the turbulence in and out can be stressful (especially coming over the mountains), but intermittent (sometimes it's fairly bumpy, sometimes very smooth).

I never check-in more than 90 minutes before my flight, even with checked baggage-and always have extra time. Depending on the fare you choose, you can get a free checked bag, which would be nice, then you wouldn't have to lug it around DEN when you eat. If you upgrade to a Stretch seat (available stand alone or in an upgraded fare) you would be among the first to board and overhead storage would not be a problem. Those Stretch seats are really nice and roomy and your TV might also be included in your fare.

It all depends on the fare to me. Sometimes another airline is a bit cheaper non-stop than F9 is with a stop in DEN!

I hope you give F9 a try! Have a good flight!