For the most part, there is not good evidence for taking the cervix or leaving it. In my own opinion, it may depend on the skill of your surgeon. It's difficult to know exactly where the cervix begins and the uterus ends, so that sometimes leaving the cervix means leaving a part of the uterus and uterine lining. Then bleeding can occur.
It may be true that there is more chance of vaginal prolapse after total hysterectomy (removing the cervix as well), but I don't think there are good studies to prove it.
Fibroids don't usually form in the cervix, although they can. I've never seen growth of fibroids in a cervix that was left after hysterectomy.
As long as your Pap smears are normal, chance of cervical cancer is almost none.
There is a good article here about leaving the cervix or no http://contemporaryobgyn.modernmedicine.com/contemporary-obgyn/news/hysterectomy-will-ruin-my-sex-life-orgasm-will-never-be-same
If it was me, and I had a good surgeon, I'd probably choose to keep the cervix. But I'd be happy either way.