We fly JetBlue. I'm not from Detroit, so I can't give you great buy-prices from there, but I would definitely check into JB.
Reasons we love JB:
--Full-size Airbus planes (3 seats per side row, and 25 rows; no puddle jumpers!)
--Assigned seating (I hate the cattle call that Southwest does, especially with kids)
--Often 50% lower than Southwest, which is traditionally the "cheap" airline here, excluding Spirit and Frontier (I paid $64 for my upcoming trip from Portland with JB; SW wanted $128 one way, and $145 back home).hd
--Free snacks and drinks (and healthy options with these!)
--Back of seat entertainment includes TV, music, an "are we there yet?" map setting, and (for a small fee) movies. There may be more, I can never remember!
--They fly into LGB, which is a small, easy to navigate airport with only 14 gates. It's less than 30 minutes to
Disneyland from the airport, and there's no waiting for transportation--$45 cabs are right out front. There's also not that frustrating 30 minute wait for your luggage like at many other airports (we once waited 45 minutes for our luggage to *start* at LAX!)
--Staff is generally laid back and helpful (except for the luggage marm outside TSA at LGB that sometimes makes you put your barely-too-big carry-on in the size checker thingy and then makes you check the bag when it's too big by an inch, but that's only happened once in like 10 flights out of LGB)