The keeper vs Franklin Richards
The keeper=>Basically, in the alternate future timeline of the Guardians of the Galaxy, the Surfer acquired Quasar's Quantum Bands, fullfilling his destiny as the protector of the universe; the ultimate "agent" of Eternity, in retrospect. During a battle with Galactus, the Big G was finally fed up with his ex-herald, so he stripped Norrin of his cosmic glaze and powers, and destroyed his board. Drifting off in the void of space (and kept alive only by his Q-bands), Norrin was rescued by a young Watcher by the name of Aron. Aron took Norrin outside of the body of Eternity, and (much like Yoda and Luke Skywalker), Aron trained and taught Norrin to use Q-bands to the maximum potential; far beyond anything Quasar has ever done with them.
>Aron also revealed to the Surfer that the power cosmic still layed *within* him. Norrin eventually came to accept this truth and re-coated his body with the silver glaze--at this point, he renamed himself "the Keeper." Returning *into* Eternity's body, the Keeper's duty was to protect all life from Galactus (as an old friend once called him, "the Anti-Galactus"😉.
>Since the Keeper only appeared (IINM) in 2 issues (GUARDIANS OF THE GALAXY #24 and 25), we never really got to see the full extent of his abilities/powers. But if you put 2 and 2 together (the Surfer's Power Cosmic + the Q-Bands utilized to their maximum potential), you can kinda figure out that the Keeper must have been pretty powerful. I do remember the Keeper being able to *freeze* time, perform warp-quantum jump (ala Quasar) faster than Norrin's own speed could have ever taken him and shield himself from detection by other cosmic beings like the Watchers and even Galactus. Basically, the Keeper was a vastly beefed up version of the Silver Surfer (vastly amplified cosmic powers, amplified energy blasts and manipulation abilities, etc.). The Silver Surfer boosted to his full potential (kinda like the Pre-CRISIS Superman reaching his potential when he wielded "the Sword of Superman"😉. I'd conservatively *guess* that he was at *least* as powerful as Tyrant, any Watcher, or any Skyfather; some would argue that the Keeper was on par with Galactus himself (which I guess would make sense...since he was supposed to be Galactus' opposite number. The Keeper was able to defeat a *weakened* Galactus in battle); again, difficult to say for sure given his brief history. I would go with the conservative estimate of Skyfather/Watcher level power.