I have done some analysis of the data from this highly scientific survey
The results are not surprising. In order of popularity, based on average scores:
Circuits
Le Mans 9.8
Sebring 8.9
Spa 8.0
Silverstone 7.5
Fuji 6.8
Shanghai 6.1
Categories
LMP1 8.7
GTE Pro 7.3
LMP2 6.9
GTE Am 4.1
LMP3 3.4
Series
WEC 8.2
ELMS 5.5
MLMC 2.1
ALMS 2.1
ALMSC 0.8