Hope the cats are at least 5"...cuz any smaller than that and its possible they will become food. I would be worried about the pbass as well, as they have a crazy fast growth rate, and can get large enough to eat some pikes.
About the pikes you want, i wouldn't do it unless you were adding more than one pike. Because adding just one to a tank that already has an established 10" pike is basically settin the new pike up for a serious beating. When I got my strigata a while back, I introduced them TOGETHER to a new tank, they had never been kept together. The female was about 12" the male was about 10". The minute they saw each other it was game on. It good so bad I had to seperate them with a divider for a few days. Point in case, you will have aggression if you try adding ANY pikes to that tank that already has your established 10" pike in it. Groups will cut down on the aggression though and help out quite a bit.