If you want to have kids, in my experience, have them at a biological responsible age so that you don't have to deal with all the stuff that comes with kids at older age.
Career is not a race. You can easily coast for a while and have kids and come back and crush it later. My wife took a back seat in her 30s and we have 2 healthy balanced kids and she is crushing it in her early 40s.
Wife's TC: 300