My ideal scenario would be a year off for mat leave, and return 2-3 days a week for my sanity and financial independence. I would personally not feel comfortable with not bringing my own income in, even if I didn't need that income.
But that attitude is shaped by my own life experiences, and witnessing what my own mother went through. Not everyone will feel that way at all, which is absolutely fine.
It has to feel right to you. You might not want to return to work when the time comes - and certainly you are lucky if you do have the choice. I'd just take it as it comes. If worst came to the worst and you needed your own income, would you be able to get a job easily enough?
Sadly, I will be working FT forever. I suspect :(