Hello Steve,
I will try to answer your questions:
1. As far as I know, you either have to change the radio settings or the control surface deflections for each airplane. I do not find the airplanes extremely sensitive overall though. Do you have this problem with any planes in particular?
2. Not as far as I have seen.
3. I have not looked specifically for park flyers, but I have seen a few around. You should have the Fundango and BLT included with G2. Addons vol 4 has the Tutor included. I have also found a few park flyers to download from the swap page at
http://www.realflight.com. I think I got a small Cap 232 there. I am not sure how accurate they are though, as I have not flown any of them outside G2.
Best regards,
Krister