I completely agree S66: I wasn't trying to make an argument either way, but really, my gut does tell me that he's somewhere around Plagueis' level.
But, of course, so can everyone say about anyone.
Regarding feats and accolades, Sidious would slaughter Revan completely, I agree. Had Fisto not had Windu at his side he would undoubtedly been blitzed.
This is Revan's best speed feat than I can find is moving in a blur while deflecting blaster bolts:
Revan was in motion, his lightsaber flashing to life, before the words had finished spilling from her mouth. As Veela and two of the others—reacting slightly faster than the rest—fired their blasters, the green blade transformed into a spinning, twirling blur as he used it to deflect their bolts back in the direction of the shooters.
-Revan
Tiin's best is moving his blade so fast it expands into a shield:
Qui-Gon, Obi-Wan, Tiin, and Ki-Adi-Mundi surged from the pyramid entrance, engaging the terrorists that had driven them back. A quarter of the way across the immense plaza, the Jedi spread out in a wedge formation, their constantly moving blades fending off blaster bolts loosed from ahead and to either side. Behind the energy barrier fashioned by the lightsabers, Yaddle, Depa, Vergere, and two of the judicials raced out to divert fire from the rear.
-Cloak of Deception
Fisto blows both out of the water, moving so fast that Kenobi saw him as moving in three directions at once:
From the corner of his eye he saw that Kit had made his way almost to Ventress, and what he saw as the Nautolan increased his efforts almost broke Obi-Wan's concentration. His companion was a living, martial hurricane, his body moving in two and three directions at once, joints flexing, unlimited by human vertebral restraints.
-The Cestus Deception
Besides, S66, you already know my say on Revan vs Maul.