Livery has nothing to do with what airline that one chooses to fly with. I would've thought it has zero bearing on ROI (though I recall reading somewhere that darker colours make the plane 'heavier' thus need to carry slightly more fuel).

The current one is nice enough and I might say the nicest out there (except for maybe CX's brush swish). Dynamic but elegant, creative yet restrained. Leave as is.

Rather BA should invest in better hard product and catering!