tell me about finances for couples

I’m a happy singleton, so I don’t know much about couple or relationship finances. I won’t let that stand in the way of an opinion though .
As far as I can tell, there are three main options (with variations) for the practicalities of joint finances:

totally combined finances, one pot where all the money goes
totally [...]

living on one income - the single life

I find it amusing when you see calculators designed to justify one parent in a family staying at home. Not because that’s not a worthy goal if it suits you, but because they are about how you can live on one income. And I live on one income. But that’s because I’m single.
Now, I’m assuming [...]

not sustaining my dream lifestyle is ok

I was writing yesterday about the salary that I’d need to support my preferred lifestyle, and it came out to be an extremely large number. This number is larger than I have the means or inclination to earn.
I could use this information to motivate me to earn more money, but more than tripling my gross [...]