If i have a female rottweiler should i get a male or female pitbull ??

i have a lovely 6 month old extremely friendly rottweiler. she is very dominant and territorail though. she protects my family soo well !! she is always happy to see people and she loves playing games ! she is very active and boistorous .. she is a sweet natured dog but i really dont know whether she will changer her attitude when she is older .. rottweileres tend to think their the boss and leader of the pack which is why im having problems deciding whether to get a male or female pitbull ?