Ditto on the Jazz passages. I have taken some of those oh so smooth passages and put a vst on that track and created some "nice" lines for country work. Especially older country, which I prefer. Probably not as elegant as Guitar Rig, but some of the free amp simulation vsts can really create some convincing sound.
I play guitar though, so mainly I noodle around on my own till I find a good melody. But, these RealTracks can be very inspiring and make a good jumping off point.
BTW, I really enjoyed reading and exploring your site Ed. Good stuff. I especially like the emphasis on having fun.