I know you are looking for financial advice not relationship advice but given your concern over the exact of who pays what percentage of the mortgage and yout worry that one spouse might 'give up their job and spend money on holidays etc' and that that wouldn't be fair, I seriously think you need to reconsider getting married!
Once you get married, your house is the family home, irrespective of who pays what percentage to the mortgage. If children are born, one of you becomes a stay at home parent and you subsequently split up, the needs of the children to have a family home and a parent caring for them will be uppermost in any court's mind, not the exact percentage each paid of the mortgage each year of the marriage. You need to get clear in your head that your family home is NOT a financial investment - it is a life investment, made to benefit the family as a whole over a lifetime shared or apart. You also need to get clear that, as marriage is theoretically for life, any financial arrangement and split that you agree now is extremely unlikely to remain static over the lifetime of a marriage. I have only been married 3 years and a parent/joint householder for 5 and we have already had a myriad of financial arrangements re mortgage/savings/day to day expenditure to take account of differing salaries, unpaid maternity leave, illness, unemployment and a decision by one spouse to stay at home, all in a very short space of time!
That apart, if I were 100% sure about getting married and in your position, which seems to be that both partners have plenty of cash at their disposal and don't seem to have worries about job security, I would
a) focus on buying a family home that you are both really happy with in an area that you like and that could adapt to changing circumstances (i.e. a growing family)
b) live life for a few years - overpay your mortgage if you want to shorten the term,
c) assess whether you want to have kids. If so, this will massively change your financial situation whether one spouse decides to stay at home or you work and pay childcare or do something in between. For a start, you are most unlikely to have the problem you mention earlier ('we won't know what to do with our weekly savings' ....)
d) if you still have spare money, then think again about how you want to invest it. That could be in property or in something else. You don't need to have paid your entire mortgage on the first property to buy another one as you seem to suggest in your most recent post - you just need to work out what, if you have spare money each month, is the most realistic and beneficial way to make it work for you.