>>>So, I need a general topic and some subtopics (what to talk about) ...
A timely and topical subject would be not just SWA, but how low-cost carriers (LCCs) have spread throughout the industry at large. Almost without exception, sucessful LCCs have been standalone entities. Even before 9/11, the major network carriers in the U.S. were hurting, as business travelers became increasinly unhappy at subsidizing lower-cost fares for leisure travelers via the business travelers paying exorbitant "walk-up" fares, and the time since 9/11 has only exacerbated that trend. Now, with 2 major US "high-cost" carriers in Chapter 11 bankruptcy proceedings, existing U.S. network carriers are looking (some, for a second time) at LCC entities within the larger airline. Some airlines have tried internal LCCs before, only to have them fail outright, or perform below expectations.
United (LCC Shuttle by United, and now a new one, code-named "Starfish")
US Airways (LCC Metrojet, failed)
Delta (LCC Delta Express, new LCC "Song" starts April 15)
Continental (LCCs "Continental West" and "CAL Lite", both failed)
American (No LCC as yet, under evaluation now)
Northwest (No LCC yet, ??)
That's all here in the USA, and the same thing can be seen elsewhere with Easyjet, Go!, Westjet, Jazz, Tango, and any others I've forgotten, and their traditional network carriers in the various countries involved.
One of the main reasons for SWA's success is that it started in the USA's pre-deregulation era (pre-1978) as an INTRAstate airline (all within Texas) and was not regulated by the U. S. Civil Aeronautics Board (CAB), but a Texas state agency. As such, it learned early-on, in its formative years, to be "lean-and-mean" and otherwise to do more with less. When SWA lost money in its first couple of years, it sold 1 aircraft (of its 4) to provide funds, and went on to run the 4-aircraft schedule with only 3 aircraft. They did it by shortening ground times to only :10, and made it work.
While the 10-minute turns have since given way to longer ground times (now a minimum :20), that same sense of resourcefulness remains, and has always been fundamental to them, and not something they had to "learn" later.
Hope this helps...
ALL views, opinions expressed are mine ONLY and are NOT representative of those shared by Southwest Airlines Co.