I couldn't agree more with Thom02099!!! Great suggestion for breaking your trips down.
California might be best enjoyed if you could manage flying your family out, then focusing on just that state, when your kids are older. That gives you more time there, and they would be at a more appropriate age for the larger cities, if that's really on your bucket list!
Just my humble thoughts based on travels with my own kids, as well as traveling cross country when I was growing up! To this day, Colorado, Yellowstone, Utah, that whole region are my hands down favorite places!!