I believe they should be couple-centered!
The best of marriages I’ve seen have been the ones where parents love their children deeply, but prioritize each other first.
My dad has always loved my mom immensely, their relationship has not been ideal, but it always made me feel happy to know that in the uncertainty of life, there was at least one thing for certain, one thing truly stable and enduring - my father’s love to my mom.
My mom often prioritized us - children, to which I often advised her against, as I believed the families are the happiest when the couple prioritize each other.
When they do so, then two people who make the family, feel happy and happy couple is better equipped to have happy children too.
I think lots of married couples shift a lot of their priorities onto children instead if themselves and I think that’s a mistake.
Happiest marriages I’ve seen were the ones, where men prioritize mothers of their children and women prioritize fathers of their children.