I would examine a few basics without going cosmic....
1. what kind of flying do you want to do? The answer to that question will tell you what you really need to know.
2. Regarding all majors, not just UAL.... How confident are you in the upper as well as middle management team? The middle level guys/gals are an important factor, for they are the next generation of upper level managers.
3. What is the culture like? Is it a good fit for you?
I wouldn't look back too far in the past as you consider what the has-been managers did. I would be looking at the here and now, and what the road looks like ahead. Another thing: I think there is another round of consolidation ahead, maybe 7-10 years out, but even SWA may merge and/or be involved in a transaction. Fuel and labor will always be the two largest cost of an airline operation. Stable fuel prices and/or a great purchasing plan equal stability. Labor stability (contentedness of labor) will be added value to the stock price, but not necessarily measured in other places. However, if you feel happy where you are, and where you are going, that's all that really matters.