I would make sure the angel is a little bit bigger. Once they get big there is not a lot in a tank that will stop them except for other angels and fin nippers (tetras, barbs, etc...).
I hate to say it, but I have tried to make compatible tanks, but usually end up buying what I like. I just make sure that I do not over crowd, and watch for meanies. Also, I try to keep fish together that come from the same part of the word, and in your case they do.