Returning to Feng Shui

I am returning to the game after not having played since 2009 or so. It’s my wife’s favorite game system and I just recently ran the test drive rules for FS 2… I think I want to run a long-ish campaign and use a lot of the books I’ve bought for the system: Which happens to be just about every book I could find on Drive-Thru as well as the in-print books I already owned.

There doesn’t seem to be an overly large mechanical difference in rules between FS and FS2- if I’m wrong could anyone tell me what I’m missing?