Ryanairs core focus is within Europe which is pretty much a single market these days. I know there are exceptions but that's why the business model was chosen.
The distinguishing factor is that Southwest values it's employees highly and treats them well. There was a good interview with Herb in both Airliner World and Aircraft Illustrated recently. He is a little reluctant to take credit for Ryanair though, worth reading if you can get a copy.
Herb,. Colleen Barrett and MOL's families all trace their heritage back to 1 village in Cork surprsingly enough. He was happy to accept acknowledgement for helping FR / Easyjet / Go and numeurous other Loco operations but his point is its ultimately what they do as he just walks them through the model.....this was Business week circa 8-9 years ago.
Comparing Southwest and FR is both easy and hard, easy as their business model is similar harder because method of operation are different.
Southwest had 1 single US market with lots of poorly served routes that it could start with where restrictions limited. Given the US Airlines were served with poor management and agressive Unions he felt better to have a Union working within the company at the start and make them part of the plan. This he did.......this was contrary to what rest of airlines were doing but Herb was noted as a smoker, drinker who did things differently.
Southwest are fun to fly with but will enter and exit a route just as quickly but they are also mindful with 1 million plus lawyers in the US they are always getting sued by whomever for whatever. Similarly they don't get US Federal Govt coming up with passengers charters etc with fines for airlines as a
PR stunt like EU.
FR will evolve its customer service over time but as an aggressive growing company it has to reach a point before it feels it can do that and given how it sees Unions have worked so well with other airlines in Europe it stays away from them big time.
Met a guy who works with lots of European airports in the last week and he made the point that many of the big airports who had a distaste for FR were now making discreet inquiries as ultimately bosses gets measured on PAX numbers. He viewed that next stage of expansion would be at more central airports where they would get lots of opportunities as its a recession BUT his key point was come the end of a recession they would be holding quite a lot of slots in key markets.