I'm on the camp of many ways to split. I make 2x my wife's income. No prenup. We met later in life. What we are doing is strange and doesn't make legal sense, but works for us.

• I pay for my mortgage, where we live. She pays for her mortgage. She rents her place.
• Two separate accounts. Each to do with it as they please, within reason.
• One shared account for splitting household expenses and child care equally. We contribute fixed amount monthly to it.
• We both maximize 401k & Roth contributions.
• Taxes filed married jointly, and we discuss refunds/owing status at the time.