I have to say that I would sell it. If you don't click with a horse within the first two days of knowing it, you probably never will COMPLETELY click with it. You may get to know it well enough to appreciate it and maybe even like it, but you will probably never LOVE it. My horse and I have a wonderful relationship, and I would never sell him even if I was starving and needed the money for food.
Anyways, back to your dilemma (sorry for the random side story). Yes. Sell the horse. He will find a home who totally loves and admires him, and who "clicks" with him. Not to say that you don't love him, but the new owners might have a better purpose for him than you, and it would be better for him to be sold to a place that wants all of his traits that he naturally has.