Flying pay is quite significant in BA. On a good month, as a year 1 F/O short haul, I can take home 4100GBP. Pay is generally between 3600-4000GBP per month. There is extra flying work if you really want it to top up your salary even more.
You
never have your roster changed and you get to bid for holidays in the summer. You get treated like a professional.
I would never choose to go back to the world of low cost.