Obito wasn't holding back, he just didn't take her seriously. There's a difference. Also, it's an objective fact that her normal AP is enough to injure him.
https://****************/wp-content/uploads/WP-manga/data/manga_61ca6ef79253a/95247da8258efcd31994d9810ab52504/NARUTO%E2%80%94%E3%83%8A%E3%83%AB%E3%83%88%E2%80%94-%E3%82%AB%E3%83%A9%E3%83%BC%E7%89%88-54---p083-%5BaKraa%5D%5BTS%5D.pnghttps://****************/wp-content/uploads/WP-manga/data/manga_61ca6ef79253a/95247da8258efcd31994d9810ab52504/NARUTO%E2%80%94%E3%83%8A%E3%83%AB%E3%83%88%E2%80%94-%E3%82%AB%E3%83%A9%E3%83%BC%E7%89%88-54---p090-%5BaKraa%5D%5BTS%5D.png
Plus, she's fast enough to intercept his teleportation after it's already started.
https://****************/wp-content/uploads/WP-manga/data/manga_61ca6ef79253a/8f650a4e1786a9efcdb616567e4372be/NARUTO%E2%80%94%E3%83%8A%E3%83%AB%E3%83%88%E2%80%94-%E3%82%AB%E3%83%A9%E3%83%BC%E7%89%88-54---p095-%5BaKraa%5D%5BTS%5D.png
And while his self teleportation is slower than the speed at which he can teleport others, it's still extremely fast. For example, Rinnegan Obito could teleport away from MKCM Naruto trying to slash at him despite them being relative in physical speed.
https://****************/wp-content/uploads/WP-manga/data/manga_61ca6ef79253a/539eda1cccde111d32932f99371faf6f/NARUTO%C3%94%C3%87%C3%B6%C3%92%C3%A2%C3%A8%C3%92%C3%A2%C2%BD%C3%92%C3%A2%C3%AA%C3%94%C3%87%C3%B6-%C3%92%C3%A9%C2%BD%C3%92%C3%A2%C2%AE%C3%92%C3%A2+%C3%BE%C3%AB%C3%AA-66---p012-%5BaKraa%5D.png
And I doubt the Rinnegan amped his Kamui more than it amped his stats, since it has no real connection to his MS other than being a dojutsu too. You could honestly make a pretty good argument for Konan being relative to Obito in speed, which is quite insane for a mostly irrelevant side character.
Understand Itachi's placement, even though I disagree.
Edo Itachi>Prime Alive Itachi. Unless ur talking about a hypothetical Healthy Itachi revived from his Edo Tensei self.
Eh, personally I'd put BZ Obito at 2nd. His feats putting him above Juubito come from when Obito took control of him, and him stabbing 3 Eyed Juubidara was offguard.
"just to barely beat"
https://****************/wp-content/uploads/WP-manga/data/manga_61ca6ef79253a/5c5930ddc2666435108c2e8c68e03f6f/NARUTO%E2%80%94%E3%83%8A%E3%83%AB%E3%83%88%E2%80%94-%E3%82%AB%E3%83%A9%E3%83%BC%E7%89%88-58---p124-%5BaKraa%5D.pnghttps://****************/wp-content/uploads/WP-manga/data/manga_61ca6ef79253a/5c5930ddc2666435108c2e8c68e03f6f/NARUTO%E2%80%94%E3%83%8A%E3%83%AB%E3%83%88%E2%80%94-%E3%82%AB%E3%83%A9%E3%83%BC%E7%89%88-58---p132-%5BaKraa%5D.png
Literally took less than a minute once Itachi joined the fray lol.
And how was Nagato disabled? He'd already regained his mobility after absorbing Bee's chakra.