Wills and second marriages?

Those of you who are remarried, with children/ young adult children how did you handle your estates. We need to update our wills, and I have heard arguments both for leaving it all the the surviving spouse, then going to the children in equal shares, and dividing it equally between surviving spouse and deceased spouses children. I see the fairness of the latter on the surface, but how would the surviving spouse pay the bills with such minimized funds. In our situation we both have life insurance policies divided 50 percent to survivor spouse and 50 percent to child/children. We each have two children. What about other marital assets? All to spouse, divided into thirds or some other formula. Our children all all roughly the same age, mid to late teens not yet in college.