Mon Cal was awesome, but disliked by many due to the amount of teamwork it required. You'd have a team of rebels capture a platform, leave it undefended, watch it turn grey and then get captured, and go 'wow, this map stinks'.
I think the map was great. Naval combat, air combat, limited infantry encounters, that lone anti-aircraft gun on the tiny island near the eastern edge of the map... pure joy.
Playing defensive and guarding a control point rather than trying to take some enemy-held flag is not popular amongst... certain people.
"One of the bitches actually gave birth while she was attacking, and her puppies joined in on the carnage."
--the awesomeness that is Boatmurdered.