Similar situation with earnings and ages here, along with FTB status, but reversed: I'm younger than DH. Childfree by choice. Not married. Been together 14 years.
I put all my extra money into my pension. So if we split that is mine. My pension has (and will always have) a lot more built up in it than the house. I benefit from tax relief and interest. If I want to pay off the house early I will withdraw my 25% tax free from the pension. I plan on early retirement (at 55-57) unless I lose my job or similar.
We own the house 50/50, but in reality I saved all the deposit (30k) and pay the mortgage. We don't do a "split" with the finances, more like "one pot". I make sure all the bills are paid. He mostly pays for food and days out. But I keep and spend my bonuses as I please. He keeps any extra money he has month by month to spend as he pleases. My bonuses tend to go on joint things (e.g., holiday, car repairs, campervan, house deposit) - I haven't been in this job THAT long, so I want to start saving my bonuses more deliberately, although that has been hard so far.
Because I earn so much more than him (4x his salary) I don't mind if we split up in the future and he gets half the house. He would need it, and he has contributed in his own way as much as he can. I still have my pension and high salary.
Plus, in our situation, I think it would be unfair to make him pay for "consumables" (e.g. food, days out, rent) whereas my contribution was ring-fenced as an investment.
I'm not saying you do the same thing as me. But I like the idea of proportional ownership of the house in your case if you do want to ring-fence your finances. This way, he is still building up an investment for himself in case things do go wrong and you split.
Is it fair - if you split in 10 years - that he has nothing to show for it, despite contributing for many years into the household relative to his income? Especially as unmarried people, he would get none of your pension savings (which you say are "for us") and none of your other savings. Having a share of the house so he can get his own place feels like the bare minimum.
I'm sure, on his side, the psychological power balance would feel better too. This was another reason why I wanted my partner as an equal owner. In fact, he loves the house so much, and has done so much to it (DIY, sorting the garden, laying floors, painting, decorating): it wouldn't be fair - in an argument/split - to say "this is my house, I pay the bills", which feels like what the "rent" suggestion is implicitly implying.