Kamui, by far.
Rinnegan's defenses (Shinra Tensei, Preta Path) can't stop a long range Kamui snipe (which isn't a phsyical thing but a space-time hole so it can't be physically repelled with Shinra Tensei and it isn't something made of chakra but only activated by the chakra in the eye, so it can't be nullified by Preta Path's chakra absorption, not to mention that Kamui snipe worked even on Gudodama and that was when Kakashi used it before receiving Rikudo chakra). Also nothing the Rinnegan can do can stop someone who teleports himself with Kamui, or approaches by phasing through everything with Kamui.
Rinnegan's offenses can't hit a Kamui user, everything the Rinnegan can dish, no matter how powerful, can be avoided by simply phasing through it with Kamui. Not to mention teleporting one's self in the other dimension or using long range snipe Kamui to warp the incoming attack.
Basically, Rinnegan can't do shit against Kamui while Kamui works greatly even against Rinnegan. Before someone says "well there's Rinbo which you can't even see without the Rinnegan", Rinbo was a lot slower than Rikudo Naruto and Rinnegan Sasuke, they could easily dodge it or react and fight against it; the same Naruto and Sasuke were outspeeded by Kaguya's S/T, it was too fast for Sasuke to do anything against it, and Naruto could barely dash away to avoid it. DMS Rikudo Kakashi's long range Kamui was used so fast that it outspeeded Kaguya's S/T completely, saving Naruto's life in the situation. So Kakashi can use long range Kamui to one-shot Juubi Madara before Madara can use Rinbo to one-shot Kakashi. Not to mention that with knowledge Kakashi could just camp in his Perfect Susanoo or rest phased.
Last but not least, just compare DMS Rikudo Kakashi with all the Kamui powers enhanced by Rikudo chakra vs Rikudo Sasuke with Rinnegan enhanced by Rikudo chakra. Kakashi's performance with DMS Kamui against Kaguya is like a thousand times better than Sasuke's one with Rinnegan.
