You can ask the current owners about the "misplaced aggression". Specifics might help you determine if the bird is a match or not. I would also highly consider keeping the bird off of your shoulders for a good long while, or perhaps never allowing it there, depending on what this aggression is.
Birds tend to realize when their former favorite person is gone. They grieve, then they pick a new favorite. I doubt a ten-year-old senegal would outlive you, though, unless you expect to die young. I am fond of telling Roni that she has to "go out" with me unless she is going to start being nicer to other people.
My kids also tell her they won't take her, but, seriously, I doubt she'll outlive me, and I'm older than you are, but if she does, she will adjust to someone new. She is great with my vet and with the people at the bird store. In fact, though she loves to lure my daughter, second son, and a few others over and then give them a nip, she has been very sweet with my oldest son since he had to move back in for a few months. (She is smart enough to know not to burn ALL of her bridges.
I've heard a lot about senegals going after other birds, but Roni doesn't. She avoids other birds, but doesn't push herself into their space. She is fully flighted now, so she could make a pest of herself if she wanted to, but she doesn't. In fact, Joelle tried to go after Roni a couple of times last night and Roni actually fled.
I expected I would have to reclip her wings, but when they grew out this time she didn't even notice it for a very long time. When she finally realized she could fly, she took a few flights to kind of get her navigational skills back, and then settled down to barely flying again. Now, she only flies when she is startled, and, frankly, as strange at this is going to sound, I think it has improved her confidence to be able to fly off when she is afraid, thus resulting in a bird who actually bites less. If she would start to stalk other birds or people, she'd get clipped in a heartbeat, but, for now, I've decided to let her build up her confidence.