Birth control or cycle tracking?

M24 F24 married

We are weighing options between focusing on trying for a kid, having threesomes and solo for her, and both. I’m pretty afraid of another guy getting her knocked up, and also really wanting a kid right now. She also wants a kid, but is valuing threesomes and solo sex with other guys a little higher right now.

Obviously we can have our cake and eat it too with cycle tracking and no BC, but in y’all’s experience how safe is that? I do think birth control is the more responsible option, but I’d almost rather quit entirely than do that. But that would make her very sad as well