U hire people to get work done 4 U,not the other way around

With all sincerely, you talk tough here, and appear to have what it takes to build up a team, where you really have to consider personality conflicts. But now it is only about an assitant.
General hiring policy of the company is always picking talented and manageable ones, so you have to decide what is best for you given the circumstance. If you really plan to grow your career, dealing with UR assistant is just the beginning of much bigger role down the road.