I agree with new wheels...all in one's personal taste. As far as exterior paint care, there are excellent websites with "how to" articles. This link, Larry from Car Care Specialties, is a PCA supporter. I have been to clinics where he demonstrates how to use different products and why.
http://www.carcareonline.com/
As far as your buffer, if it's not an orbital with adjustable speed, toss it and get a Porter-Cable; you'll do more damage than good, especially on a dark car.
Regarding your top, how is the canvas? After ten years, it may not be so good; why replace the window when you can have a new top with glass installed for not that much more these days?