My first observation is that angelfish are a shoaling species. But here we have something quite different from say characins, or cyprinids. There has to be a group sufficient to avoid stress, but there is the added difficulty that this is a cichlid and the males are territorial. I would consider from my research that five or six is absolute minimum. But to be fair to the fish, there should be double or more. They have been observed to form shoals of roughly 30, but this is in the expanse of a stream or flooded forest. This means a very large tank, because pairs are likely to form, and the other angelfish won't stand much of a chance unless the tank is sufficient in size, and even then it may not work. I do not believe in keeping fish that cannot be provided with what they expect. That is simply inhumane. The stress we cause fish is the reason behind much of the disease issues.
This video is worth considering. The group of 11 angelfish are in peace. Yes, there is jockeying for position, but that is normal and circumstances must provide for it. I've forgotten the tank dimensions, but the poster down in the comments says he thinks they are due for a significantly larger tank.
Edit. Forgot to mention that a bonded breeding pair is a very different thing. Depending upon their size, this tank might suite them, alone.