Giving up Smart/assets for Capela is a backwards move. Posters on this board are starving for gaudy rebound numbers, but Capela is not it. The Warriors exposed him (he can be guarded by wings because he doesn't have a post/inside game and he isn't a great perimeter defender against wings either) and it's going to be exploited from here on.
I agree with Silky's suggestion of taking a flyer on Poetl, Maker, Noel, or Collins (in that order) before giving up anything for Capela, let alone one of the leaders, mentors, and a top defensive player in the league.