Blood parrots tend to be rather aggressive, at least, in my experience. I wouldn't recommend angels bc the blood could easily rip their delicate fins. Although blood parrots are genetic modifications, and their mouths are typically too small to really "attack" most fish, they definitely can use them as battering rams and beat other fish into submission.
It really all depends on how large the blood parrot is, etc. And from your post, it's hard to gather some needed info for your question... like, do you already have the blood parrot, or are you just thinking of getting just one?
If you're looking for tank mates, and you're dead set on a blood parrot, you might want to consider just getting two bloods and then a larger pleco for your tank, give the bloods TONS of hiding places, and call it a day.
Let's see what other people think, but from what I've dealt with bloods, they can be snotty little bastards and pick on other tank mates, even if the tank mates are larger than the blood.
