Me and DH have always just split things relatively 50:50 as we earn around the same.
We have a joint account that pays bills, household things like food ect.. and then we have our own separate accounts for our own spending.
However, I'm thinking of suggesting he starts putting more towards things. He has two older DC who are teens and are currently eating us out of house and home. I do all the shopping usually and it's ridiculous the amount they are getting through. I think DH should put some more in the pot to go towards the additional amount of food we are buying every week.
I think this is more than fair as I do tend to spend more on our joint DC for their hobbies, treats, little bits throughout the month from my own money ect.. as I spend the majority of the time with them.
It's annoying me that I seem to have less and less disposable money every month as DSC are getting older and wolfing their way through the cupboards all the time (here 50:50).