I know that everyone says that OPOL is the gold standard etc. And if that's the only thing that works we'll do that
BUT
DH and I are both bilingual, in the same two languages. DS has two cousins who are also bilingual, and an uncle who is bilingual, and an aunt who is pretty much bilingual. All of us in French and English. And when we're together we all speak whichever language we want to at any one point. Even the rest of the family, on both sides, understand/speak both languages to a greater or lesser extent.
Basically we would like DS to be bilingual because we're bilingual, not because arbitrarily I only speak English and DH only speaks French, because that's not an accurate representation of language in our family.
When DS goes to school we intend to switch as a family to the other language as a home language. That's what DH's brother's family does and it seems to work really well.
I'm not really sure if that makes sense, but has anyone raised bilingual children by being bilingual?