If you have a plan for culls that have quality of life issues (bad teeth, joint or eye issues, things like that) then go ahead and line breed her, but plan to use an unrelated buck for her offspring, assuming you get keepers. If the offspring are not steller but still pet quality then you know, and do not have to repeat the breeding. If you get actual defects though, you need to know that you can euthanize them, or that someone will do it for you. This is true with any breeding but doubly true of line breeding. I have a hungry dog that will eat my meat rabbit mistakes, but if you are ethically opposed to any euthanasia at all, I would hesitate.
EDIT for clarification: The dog gets the dressed carcass, NOT a live rabbit. I perform the euthanasia, not the dog!