I don't make any claim that it was the best of the series, by any means, but personally I really, really, really got into FOF 2001.
I played a lot of dynasties, messed around with house rules, and got very immersed into the nuts and bolts of the game. This was before deep playtesting, multiplayer, etc -- just a different time.
FWIW,
my favorite dynasty from FOF 2001