well the issue i was refer to exactly is where the lower stage doesn't clear in time, so the exhaust from the boosters pushes the spent stacks into the rest of the rocket before you can clear it. Jeb's lost a lot of his 9 lives to that one....
Actually focus on doing things and going places. Instead of you know, just adding moar boosters. And i find i'm making much more ethical decisions when it comes to sending a Kerbal vs sending a probe.
Just the Mun and Minmus. The limitations on career mode actually helped focus me quite a bit. Instead of just building the biggest possible rockets, now i actually build them to, you know, do things.