Hey... figured I'd post an update should anyone need info.
Midwest Airlines was
awesome when I went to Boston last week. I travelled via Milwaukee, which is a great alternative to both O'Hare or Midway, which is usually what happens for us Minneapolitans.
First up, I was not the only gimpy person on three out of four of my flights. I had my manual chair cared for very well on each flight, and I watched a lady with a power chair get on the plane from Milwaukee to Boston - and I also watched the care they gave to her power chair as well. They were very professional getting her onto the plane, as she needed a full transfer. The staff also gave plenty of help to a man who was a double amputee, and got him on and off the plane without any trouble. The stewards/stewardesses were so friendly and wonderful, and the pilot came out afterward and said hello and asked us how the flight was, basic chit-chat. No one ever made me feel rushed, which makes me feel a lot better about being a slowpoke!

The only thing I wished was better was the very short amount of time they allowed for a 'preboard'. On the way back, I had a hard time getting settled in before everyone got on the plane. Plus, the staff didn't keep folks that were obviously not up for the preboarding specifications on the flight from Boston. So, in effect, putting my carry on, my crutches, and my wheels where they belonged for the flight was way more difficult because I was trying to fight with others for overhead space, to untangle my legs and that sort of thing.
But... considering my last trip to Boston on United via Chicago O'Hare, this was loads better.