Pat Lawlor designs are so creative that if I had to pick one, he would be it. Although he isn't an outright winner for me, he really does some amazing things in a limited amount of space.
RBION is an absolute ball tearer of a game that I just love to bits.
I also think Steve Ritchie designs are waaaaaay over rated and does not deserve the accolades he gets.
All the forefather designers deserve a big round of applause too as I loooove simple, easy to understand, geometry designed games from the electromechanical era.