Do keep in mind that other complications can happen too. Small breeds are very popular but are prone to having stuck kits, which means the rabbit needs a c-section and a spay quickly or she could die. Pregnancy toxemia, uterine infection, and mammary infection can also occur and are very dangerous. There are also problems with runts, peanuts (genetic runts of dwarf breeds that are too misshapen to survive long), enterotoxemia, etc.
New mothers are not only prone to injuring their own kits, but also to birthing them outside of the nest. Even if the rabbit is living indoors, this can result in the death of the kits if they aren't found soon enough as they can't keep themselves warm.
If you are serious about breeding, you'll need to do tons of research as well as finding a nearby responsible, experienced breeder to act as a mentor for you. You should also join the BRC, and keep in mind when planning litters that there are thousands of rabbits in shelters and rescues. Can you screen potential new owners well enough to be sure your babies won't end up in a shelter too?