I love many of the trios mentioned so far. My answer would change weekly, but today I'd select:
The Addams Family - NicoVolta spent some time explaining this pin to me at the Roanoke Pinball Museum and I finally understood the hype.
Quicksilver - I loved this one at TPF a few years back when dothedoo brought his to the show.
Galaxy - my wife likes it best out of my current collection.
It kills me not listing an EM. Dixieland, Jet Spin, or Wiggler would really round this list out properly if I could have 4 pins.
List will likely change next week.