I agree with others that you need to base it on personalities and there are never any guarantees.

Working with a rescue organization, such as Jen's, is a good idea because if, after a good period of time and following all their suggestions, you do end up with badly matched cats your new cat can go back to the rescue to look for a home that suits them better.

As long as Butler is what I call a "soft" male, either male or female should work. You will need a youngish and lively cat because an older cat or one who prefers a very quiet life is not going to appreciate the combination of settling into a new home and dealing with a rambunctious resident cat.

You might want to look at what you liked about Princess, and Butler's traits, and what you particularly like or don't like about individual cats. For instance, one talker in my house is enough for me and when I have two talky fosters I have to shut myself in the laundry room to get away from the noise sometimes. I don't really like cats who like to strop my ankles all the time since I'm always rushing around and they make me fall over. I love independent cats and those who are simply good companions and don't have time, literally, for lap cats. If you get another cat who is 2-3 years old, their personality will be very apparent.

I'm glad you have chosen to rescue.