I'm torn between two now. First off, I want to say there are a lot of good instructors out there and they all have the niche's that make them good guys. I'd say that AFC Adam Lyons is an obvious choice. He is very very good at what he does and his students are phenominal from what I hear. Despite being married he is still very active helping people and attending seminars.
Also, Jon Sinn would be my second. Jon can break down game like nobody's business. He worked under Mystery for years and was the lead instructor for Mystery Method then he worked with Savoy. From there he's mastered his own techniques and single night lays with the help of Capt. Jack some. His obsessive nature allows him to be able to break down any instructor in the communities game and analyze like you wouldn't believe!!! From what I hear he genuinely cares about his students and follows up with them too. He has a great blog by the way.
http://sinnsofattraction.blogspot.com
I personally have learned SO MUCH from reading Sinn's blog that it's melted my brain and reassembled it a few times. His takes on the community and "game" are definitely his own and are well thought out.
With that being said I'll mention some seriously under rated PUAs and instructors in the game today.
-Doc Holiday (this young man is a day game master)
-Speer
-Psych (I've heard interesting stuff about this guy, he's on his way!)
-Bravo PUA (Amazing stuff for online game)
-Steve Mayada aka El Topo (his red stack is awesome and his ability to go sexual is amazing)
-Capt. Jack (the pirate king is great a single night lays and taught most of the best instructors in the business how to master it as well)