To be fair, there is also a large number of fans who are happy J/C did not
IMO, at the very very very least, she could have had a thang with an alien fellow (or lady) who stuck around. I could have rolled with that, and it would have avoided some of the problems that J/C might have encountered had they actually gotten together.
Although I do wonder sometimes if she's not meant to be "happy" as a character. Every alternate timeline seen in the show ends poorly for her (dead or Forever Alone.)