Pros
People are nice for the most part, supervisors are helpful. I would suggest finding a good behavior consultant to work with and taking on their clients - many BCs are either overworked or incompetent, so if you find a good one, stick with them.
I learned a lot about the behavioral/mental health system which helped prepare me for longer term goals - writing progress notes, interacting with parents, teachers, and other professionals, etc., the insurance racket, using EHR system, etc.
Cons
Personally I think independent contract work in the mental/behavioral health field is a total scam (it has been effectively outlawed in NJ). My hourly rate was not a livable wage, and I would not have been able to accept it had I not lived with my parents at the time. You are only compensated for direct client contact. You need to complete progress notes and billing paperwork in order to get paid - this is often hours of extra work each week that you are not compensated for. You are also not compensated for travel times, gas/mileage, etc. Even worse, if you show up at a school or daycare to find that a kid is out sick and their caregiver forgot to tell you, you will not be paid at all - this happens pretty regularly if you have a lot of clients and is a huge waste of time and your own money. Oh, and you need to complete 20 hours of continuing education each year that you are also not paid for.