Caedus could very well be No.1.
But, as I said, to make a list, you need canonical facts backing up your argument./
Took on multiple Jedi and Battlemaster Kyle Katarn and outfought them. He even managed to nick a few hits on Luke, which is pretty impressive.
He was an extremely strong person in the Force. Very good at Force Influence, able to make powerful Force-Users with all their resistance and powerful will, obey him. He could heal himself on the spot and adjust his body to get use to the enviroment.
He Achieved Oneness. He could Absorb Energy and deflect it. And he could render himself so that he was extremely difficult to sense in the Force. Solo was able to force his mind into that of another through the Force, imposing his will through the Force. (As seen when he helped his mother with landing the Millenium Falcon. Boomshackalaca!)
He learned Shatterpoint, and you should read the novel "Shatterpoint" to see just how awesome that ability is. Able to see the weakness in pretty much everything.
Thats my reasoning behind Caedus, I'll make top 10 list of both jedi and Sith in a couple hours...
P.S. Wookieepedia is an OK source right?