I thoroughly enjoyed reading your thoughts and experience of ECU flash. Your riding impressions and results mirror my feelings after having my KTM "flashed". Flexibility and refinement were the biggest improvements I felt, though the the extra mid range push at 6000 to 9000 rpm is very exhilarating and intoxicating.
MPG is very acceptable still for a 1200cc V twin, motorway slogs see 60 mpg, progress on A and B roads sees mid 40's to low 50's.