If you were a Breeder and knew what you were doing it would be very different.
But she is very small and it could be very dangerous to her health. You wouldn't be able to breed her untill she turns 2 because she is so small. I think it's best to have her spayed, and leave the breeding up to the Breeders who have the experience needed. They do not change because they were spayed. They are still the fun loving babies they have always been.