From what i've seen blood parrots aren't that aggressive and when they are they have such... peculiar mouths that all they can really do is chase and flare. african cichlids are built to do damage to other africans. they have effective jaws and loads of chisel like teeth to skin their opponents alive. Also take into consideration that african cichlid color signals are different then american cichlid color signals. When an african cichlid is dominant it will become bright and vibrant, the losers tend to darken up and display bars. with american cichlids the symbols are the opposite, with the top cichlid becoming dark to display the spangles vibrantly while the lessers will bleach out. If an american looses to an african cichlid then when it tries to say i surrender to the african it looks like it is saying "is that all you got wuss" and vice versa. the other issue that is against you is that africans generally scrap it out constantly aside from a few exceptions. this is why people overstock african tanks, the dominant fish will be constantly changing targets and will be unable to focus on one individual for too long before someone else requires a reminder about who is king of the tank. Americans tend to be a little more leaniant until they snap and go on a temporary rampage, meaning it is better to let them establish their own territory and minimize incursion opportunity. I wouldn't try mixing new world cichlids with africans, especially if they are timid or known for starting a genocide at the drop of a hat.
if i were you i'd get some tough, but not nippy, barbs or tetras and maybe a red tail black shark.