Interesting observations - however, although I admire the low-cost concept of Southwest and the like, I disagree in some points:
1) They always board the aircraft from the rear as well as the front. To ensure passengers use the rear entrance they dispense with the perfectly good telescopic ramp at Stansted. Passengers must go down a flight of stairs to the apron.
I guess this is also to save money as I believe the use of the jetbridge incurs additional cost from the airport operator at many airports. However, I was recently boarded at MPL through the jetbridge, if I remember correctly.
2) At Treviso and other small airports - check is completely manual - no computers linked up to the central reservation computers in England or Ireland. The check in staff (just one!) was ticking passengers off a faxed passenger list!
Not sure if that saves a lot of money. I am led to believe that it is more cost-effective that they don't print paper tickets and use laminated, re-collectable boarding passes.
3) by landing at tiny regional airports they make money on the bus trip into town (very reasonably priced). It is a specially chartered bus which leaves half an hour after landing. This would be impossible at larger airports because the bus into town would sold off as a concession to a third pary or jealously maintained by the local transport authority!
Is this the case ? I was always under the impression - from the advertising etc. - that the bus service is provided by independent bus companies that are running their service at their own risk. At BGY, it is the same service as before-Ryanair and they simply added some frequencies.
4) At Treviso - taxying to runway takes about 45 seconds! In my case it left 10 minutes early and arrived 45 minutes early at Stansted.
5) Aircraft does not need a tow from its gate as it is the only aircraft on the apron and there is plenty of room to manoever
This lack of towing is only true for very few airports. I have seen it at any airport I have flown to with Ryanair (STN, HHN, DUB, MPL, BGY, PSA).
6) They charger £4.50 ($6.50) for a large sandwich. It cost about 50p to make a sandwich - if they sale 3 millon of them per year (assuming 1/3 of passengers buy them) then then £13 million is added to profits.
I doubt that 1/3 buys the sandwiches - my impression from my flights with Ryanair recently was that only a handful of passengers - if at all - buys food. I believe that most profits from the food and beverage sales go as a provision to the cabin crew.
7) Just three cabin crew for a 189 passenger 737-800
The number of cabin crew is regulated by law; nothing Ryanair can do about it. A 189seat aircraft need 4 cabin crew and on all my flights there were four in the cabin....
8) In flight magazine is distributed and collected at the end of the flight.
In flight magazine is a big word for that publication - it is more a catalogue that shows what is on offer for purchase. Most airlines simply keep those in the seat-pockets as their seems to be little risk that passengers take home such a publication.
The real cost-saving issues you did not mention are direct sales, fleet-standardization, out-sourcing of non-essential work, lean management structures, subsidies from provincial airports and tourist boards etc. etc.