Hi Zantaria and welcome to the board. I do not have experience with quakers, but my husband and I rescued an umbrella cockatoo who had some issues (long story) and it has turned out wonderfully. You are on the right track starting out with a smaller bird, like a quaker or cockatiel. I have two cockatiels and they are wonderful pets; easy keepers and love attention. I know folks who own quakers and simply adore them. Have you met the quaker and are you able to handle him? As to whether he would ever get better, I think most people who have rescued troubled birds will agree that with time, patience and love almost any bird can turn into a great companion, and it sounds like you definitely have this to offer. Could you be more specific on what his problems are: Is he agressive, or a feather puller or mutilator? Let us know and hopefully someone with more quaker experience will post and give you some more guidance.
Hey there. I do have experiance with Quakers. Feel freee to ask any questions you may have. At this point any attention and help you can give this kid would help but Quakers are great lil birds once they learn that you are trustworty they will love you forever no matter what. they are jsut huge loves in lil bodies. they are a great small sized parrot to start with and to handle. But it will take time and patience from you and him of course. Good luck and please feeel free to ask
My daughter has a quaker. Sweet, smart little cuddle-bug. She got him as a young-un though. As far as "re-homed" birds, they do come with baggage but they also come with a great potential for love. Sounds like your wee Quaker has found the right home.
(BTW - I hope you're not in California - Quakers are illegal to have here. But a person I know passes his Quaker off as a Conure...lol)