Revan knew how to use the light and the dark side simultaneously for insane power. He came THIS close to winning a fight no-other would ever win. Battling against the best bounty-hunter in the galaxy, the Jedi Master who killed the Sith Emperor, The Sith Emperor's former personal executioner, The most powerful Sith on the Dark Council, the greatest spy in the republic, the strongest wookie in the galaxy and the Jedi Grandmaster. He came extremely close to winning, and would have owned any of the previous indivually. He also seperately killed the greatest mandalore in history, and the dark lord of the Sith, Darth Malak. His power was crazy and immense. No question. He killed dozens of Jedi Masters with ease. Easily the most powerful star wars character EVER.
Revan came before midichlorians, so his count was not known. Plageuis could manipulate midi-chlorians, but he is only known to have done it once, and this was not much use in a battle. Revan was incredibly skilled, at a much younger age than palpatine, who at roughly the same age couldn't even defeat his master Plagueis, who was not much of a combatent compared to other Sith. Sidious could not disintegrate Skywalker, a naive jedi with roughly a few years of training, but Revan could instantly kill/disintegrate one of the Galaxys most powerful Sith, with force lighting
Darth Sidious, for example, was said to have known, or known of, every Force power in existence. Anakin Skywalker has the highest known Midi-chlorian count of all Force users. Darth Plagueis could manipulate midi-chlorians into creating new life, potentially giving the user immortality. While Revan was exceptionally powerful, some others surpass him.