I would skip repulsion. As cool as it is in concept, it makes SO MUCH FRIGGIN NOISE when it's active. I used to use it as a knockdown field for my melees, but then got so many noise complaints that I decided to get rid of it entirely.
I have to wonder... Why the hell not? The abilities are close to useless on other powersets as well. Why not buff them universally so they can be used in a team setting where Defenders are supposed to shine?