So yes …the £24,000 person should be making more of a financial contribution, is that the general feeling?
Not my feeling. My feeling is that there is nowhere near enough info to tell.
One way to split this would be to pool all the costs (including the nursery fees) and split them 1/4 and 3/4. 'Costs' should include all family expenditure, including similar level pensions for both adults.
Then ON TOP OF THAT, you need to balance the hours workedwith childcare and household. So, for exmple, if the person working PT is doing 20 hours a week and the FT is 40 hours a week then the part-timer (for want of a better term) should do around 2/3 of the childcare and housework. The full timer should do around 1/3.
Any left over money after costs have been paid could be pooled, split into 2 and handed back to each person as personal money.
That way, no one is doing better (long term or short term) than the other because of family workload split or commitments.
But, of course, this is just one way of spliting it and makes some huge assumptions. Which is why more detail is needed.