Ugh.
I agree in theory with the 'marriage should just be a standard, customized contract in the eyes of the state'. But would this cause trouble with things like getting private insurance companies to recognize wives as dependents? I suppose they would have to go into the individual marriage contract and see if she was enough of a 'dependent' for their companie's standards. I suppose semi-standardized marriage contracts would evolve, though (i.e. 'standard contract xyz' generally used by roman catholics, 'contract zwy' used by a lot of pagans and atheists etc.)