I could tell you more about senegal parrots.
While they aren't to be known as nippy (like conures, for example) their bite HURTS. Don't be fooled by their size, when I say that their bite can hurt, I mean it. Not piercing the skin yet leaving a painful bruise for a few days, or simply mauling the heck out of you. In the FB senegal parrot group I remember there was a member who's adult daughter had a fracture on her thumb from the sennie's bite. OUCH. Also my partner has quite a few scars from his senegal when she hit the terrible twos. Bites from a ringneck, emma's conure. green cheek conure, budgie, cockatiel and senegal, senegal wins by far. Got bitten quite a few times, mostly by accident and those hurt for days. So be warned. Also they litteraly have cobra reflexes. While you can read from their body language if they are telling you to back off, in my experience they are far more sudden.
If you can, go for an adult/a rescue. I know I would if I were to get a poicephalus parrot. Also another minus is that they are known to be one person birds, and even in the wild they are prone to change their breeding pair suddenly, meaning they might change their favourite person out of the blue. My partner's sennie is very well behaved and is very friendly with everybody. While she does have her favourite person, she is cuddly even with strangers.
Not to deter you from getting a poi, they are absolutely wonderful all in all. If I were to choose a certain species I might go with a red belly or a Meyers. They are smaller than senegals, and bit calmer, but equally spunky. Sadly rarer too, hard to get. Pois in general are great flat birds as even in wild they don't fly miles to no end but rather dash in short distances. Also they aren't as noisy or loud compared to other parrots. Our sennie is exceptionally quiet, but she can let out a painful shrill if she chooses to.
Be warned that pois are exceptional chewers, so loads of wood will be needed. Best way to learn about a parrot is simply to read about their behaviour in the wild. You can see by their huge beaks that it's meant to destroy stuff and make holes in the tree trunks

Or destroy your furniture if you're not careful enough (then again, my budgie destroys my furniture too, just the sennie does it MUCH faster.)
Another thing to keep in mind with pois. They are NOT big flock birds. Unlike conures who like being in a huge heaps of fluff with 10 other birds on them, pois are more solitary like. While they could live in harmony with other birds, it's bit hard as they absolutely want their private space untouched. So a nagging budgie could end up without their toes, which happened to us. While they will not chase each other, getting too close could end up in another bird getting hurt. Sennies do quite well as solitary birds. Another thing is adding another sennie after 4 years, don't be so sure that the 2nd sennie will be accepted. Most likely not. If you wondered, while they do fly in flocks in the wild, the flocks are not really packed. They fly in pairs, and respect each other's personal space.
If you can get the book from Athan and Deter (authors) "senegal parrot" you could get a further insight on the matter.
Aaaaaand this post became ultra long, sorry.....