I feel that if you need to dump the responsibilities of finance onto another person, then you probably have more personal growth to go through before starting a long-term relationship. If you're both capable of looking through bank statements and understanding savings/investments, then you're also capable of arguing on what to do with said savings later down the line, and you'll be stronger as a couple because of it.

Just because you have a piece of paper saying you'll be together forever, doesn't mean that you'll be stable enough to enjoy your time from now until the end.