I really don't get the fascination with minor variations around SOP's. Who cares? Really? The only things that matter at the end of the day are pay, lifestyle and job security. Who gets to use the thrust levers or park the aeroplane or call stop is absolutely and totally irrelevant.
Back to the thread.
The only places I would personally consider in the UK are BA, EZY or RYR. Anything else seems to me to be a gamble on long term job security. Bear in mind the "OP" is talking about leaving BA. They are not an unemployed cadet looking for their first job. However many years you have left, 10, 20, 30, 40, is anyone really confident that any other operator other than the three I have listed provide a decent shot at making it to retirement? Again I would emphasise that I say this in the context of someone gainfully employed at BA. You can afford to be picky and you must be.
Personally, I cannot imagine ever wanting to work for Ryanair. And the industrial landscape there is barely any better than at BA. You could argue it's worse. Out of the frying pan and into the fire.
That leaves easyJet.
All IMHO, obviously.