In your example, I'd say 92% LF
for 3 months makes the decision on equipment/frequency easy - keep it as it is?
I'm no expert by any measure, but I think aircraft utilisation and yield comes into it too. For example, FR
used to fly from PIK
round trip 3 times daily. I've travelled on most of the different timed flights and most were 90%+ full BUT they still reduced the schedule to one round trip per day (and suspended completely this winter!), presumably because the aircraft can be put to better use on other / longer routes with higher yields.
Remember, unlike the old days of state owned airlines that flew routes to provide a service, these days it's all about making money .... sadly!