Being from Minnesota, the answer "used to be" Sun Country because they offered friendly, warm service with (relatively) inexpensive first class upgrades, which I enjoyed. And first class was pretty nice. No more. They now are seeking to become the spirit-less Spirit of the midwest. Minuscule amounts of leg room, NOTHING included (all available for a fee, however), and maybe they will randomly leave you in a foreign country to make your own way home. So, never again on them. Now, my go-to is Delta because, duh, there really is no other option in my state unless you like a lot of connections. I find their service to be decent, you can choose a seat in advance for a nominal amount of money, and their performance record is good. Plus, they will interline you in case they run into a problem....a lot of the smaller carriers will NOT do that (looking at you JetBlue) which means you could be facing long delays in case of any mechanical or other problems. Bonus: if you plan travel far enough in advance, you can get some pretty reasonable first class upgrades, and I do that most of the time. Going to Cozumel later this month, and the "upgrade" cost me a couple hundred bucks total per traveler. The extra free luggage, food, beverages and SPACE are worth that to me. YMMV. But, the secret is to buy in ADVANCE. On popular routes, those upgrades are pretty spendy if you wait till the last minute.