I'm having enough difficulty reaching low Kerbin orbit. If anything, I'd like a mod that lets my son and I learn the basics of building and launching rockets with more of an auto-pilot flight mode. We are kern to explore more of the Kerbol system but are having great difficulty with basic missions.
If you play KSP and would like a challenge much closer to real rocketry, check out the Realism Overhaul mod—and don't forget Principia. For an actual campaign based on the Apollo program, starting in 1951, check out RP-1 (Realistic Progression).
* Kerbol is the name of the star