Mutual wills are common enough with first marriages and the sensible arrangement for a family situation, the surviving spouse can then decide what needs to be done according to the present circumstance.
With second marriages when both have “assets” they are not so often used if there are previous children.
It gets more complicated if business or other assets are held, in your case where there is a part share in property, as long as there is no restriction like a joint tenancy it will be included in the estate
As you say the surviving spouses children would eventually inherit more, so you might think it fairer to divide half each. BUT, how would the estate pay the beneficiaries, plus any expenses and tax, maybe the house would need to be sold, in fact it may still need to be sold with the existing wills.
If you would want to stay in the same house then padding occupancy for life for the surviving spouse would be good, does your husband realize the house may need to be sold.