[bena]

It depends on what you mean by "simplicity".

Combining your finances completely is as simple as you get. Money goes in pot, money comes out of pot. No separation.

But anything that gets to be a significant amount becomes a discussion. Things are no longer simple.

A joint account for joint expenses and personal accounts for personal expenses is also "simple". But how much does each person contribute? Are the personal accounts unquestioned?

The thing here is that there is no "simple". You're dealing with people, people are inherently complex. You know you. You know your fiance. Make a plan that accounts for those two people and all of their peculiarities.

It could be that it would be best for you to have 10 accounts. A house account, a grocery account, a clothes account, etc. because you need to be aware of how much you spend on food and what not. I don't know. You're going to get a lot of answers here and some of them may help guide you, but make sure any plan you come up involves your fiance and they are completely on board.