I do not think the removal of sandwiches in traveller will make the slightest bit of differance. Loads of people refuse them and prefer just a drink anyway.
The low cost carriers are not always that much cheaper if at all. If you have to pay for a baggage in the hold fee + a fee for checking -in and another fee for choosing a seat or a fee for first boarding etc. It all adds up to sometimes more than BA charge. They also have a very nice check-in on-line facility where you can select a seat and print off boarding card etc for no additional fees.
For me the airport of departure and time of flight is the deciding factor. Heathrow and City are my first choices. I am no lover of those 0600 departures with an 0500 check-in from airports that are difficult to get to at that time in the morning by public transport.