I've got a Munar Polar Probe and two Kerbin Polar Probes running with SCANsat bits, a Mun Station just after its Kerbin escape burn, a KEO Satellite, and a wide Kerbin orbit satellite. There are roughly half a dozen busted homeless craft in orbit leftover from contract rescue missions. I've been waiting till I get the Klaw to de-orbit those rather than just kill them from the Tracking Station. I haven't looked at the wide orbit or KEO Satellite since i put them up, but check in on the Polar Probes and Mun Station routinely with KAC. Everything has a KER chip and Chatterer playing. My Kerbals are gaining quite a collection of medals from Final Frontier. None of that causes a problem.
In my current save, I'm working on SSTOs and flying simple orbital rockets for training / rescues. Rescue missions require several rapid vessel swaps which doesn't cause a crashe. Nearly every time I recover a vessel, or go back to the SPH to make an adjustment to an SSTO, KSP 1.1.2 (now 1.1.3) crashes to desktop. Very frustrating, because over the course of two hours, I'll spend 30-45 minutes waiting for the game to reload. I don't even play it through Steam.
So now I've removed everything through Steam, and verified that everything is deleted from the local install folders. Downloaded a fresh copy, and going through to re-install mods one-at-a-time.
Everything but the VAB/SPH runs surprisingly well for an 8 year old 2.3 GHz AMD and the Windows XP 3.25 GB RAM limit. I've also got a 1 Gb GeForce GPU. If I could lick this VAB/SPH/Recovery crash, I don't even care that Jool doesn't sparkle.