I spent a couple weeks with "Kwaz" trying to tweak an autorate that would be a better determiner of postflop play. It became a real mess but I learned a lot from it and now have a system of my own that is a combination of "bisonbison" and what I've learned from my own research. I posted my own ideas
HERE. I don't think they are complete by any means I just posted them to open people up to all the stats you can look at and autorate by. As I say in that post I don't think any system would be perfect for every player across the board. Play with it a while and find a system that suits you, but don't spend several weeks not playing just to try and find the perfect autorate. If you like the basics I give links (in that thread) to both of the clasic autorates from "bisonbison", and "Harv72b"
Don't get caught up in it, but it can be useful if you know how to tweak it some.
Remember a read is beter then an Autorate, but an Autorate can be better then nothing at all.