Your plan sounds like the tail wagging the dog. The practical implications of this ( if one of you dies, or if you separate ) sound messy,
If you do implenment your plan, its not" we’d make A will". You would have to a will each and you can only leave assets which you owe personallly in a will, not jointly owned assets.
If you currently own your hosue as joint tenants, you will have to change this to tenants in common where you own half the house each.
You both leave you half to the children in your wills,
What happens if your partner dies
- You owe half a house, your children own the other half ( in trust probably). You cant sell the house, if you need to move, as you dont own the whole house.
As above, if there are reasons why you can't or won't get married, you need to listen carefully to your solicitors advice.