Im pretty much the same way. Im 39 and just starting collecting 2 years ago. I much prefer the last decade of games, but enjoy things going back to MM/AFM. Rarely will I spend much time on and 70s/80s machine when I play on location. My favorite old one would be Diner.
As for collecting i have 3 new sterns and a virtual to play all the old ones. I would like to get a MM but want the remake.