Perhaps we should define what is full-time employee. I am consultant, but I have only single customer/employer who reimburses my expenses without much questions. And I make similar money compared to my old corporate 9-5 job, adjusted for taxes, insurance and holiday.
I think after you hit certain level of specialization, being self-employed is the only option.
Careful spouting that off (if you're US based), it sounds like, though you're both ok with it, your employer could be liable for incorrectly classifying you as an independent contractor. You may have been aware already but if not I'd take a look at it if you're in the US.
EDIT: Checked the link in your profile, just leaving my comment so US folks are aware.
I think after you hit certain level of specialization, being self-employed is the only option.