It is apparent the crewing levels differ from base to base and airline to airline.
A while ago I flew LHR-NCE on a 319 with 5 c/c I cannot remeber the split but it was a smallish club cabin of about 20 seats, 2 c/c in club with 3 crew working in the 90 seat or so tourist cabin which was far from full (perhaps they had a large club load on the return hence so many c/c)
In contrast a few days later I flew back to LGW on a 737-400 that was full with again a small club cabin of about 15 seats but only 3 cabin crew on the entire aircraft. I in club and just 2 serving the 130 or so tourist pax. I was surpirsed to see only 2 c/c for so many tourist pax. If there were more c/c on board I did not see them.
Then again more recently I flew from LCY to Nice on a 146 on an aircraft on lease to BA with the crew from the airline the aircraft was leased from. There were only 2 cabin crew. I in club and 1 in tourist. I think the split was probably 30/70, they managed to do the job though, the a/c was about 70% full.