wrongo... you are thinking in terms of RANK... not actual ability...
Iruka's a pushover... (okay... maybe a little harsh, but come on!)
Kakashi... is MUCH more powerful than most Jounin... seriously... (oh, another thing, you can't use people from the anime, then suddenly switch to the manga...)
Shikamaru... yeah, Chuunin, yada yada... but there's NO way he'd be above Kakashi... yeah, he's smart and all, but Kakashi ain't too dumb himself... plus he's got brute strength over Shika
Zabuza... is a jounin... yeah... but Kakashi EASILY beat him in the first fight they had... and without Haku, he'd never had a second... so he's under Kakashi...
Kabuto... he's around the same LEVEL as Kakashi... he's a bit better in somethings than Kakashi is... however... I think, in a confrontation, Kakashi would win... so...
(here's where it's really outta whack)
Tsunada<Orochimaru<Jiraya... not equal. Yes, they are all legendary warriors, and are very powerful, but Orochimaru is definitely more powerful than Tsunade, and Jyriaya tops 'em both... (this is all three at their peak, not where Oro's arms are dead, Jyraiya is drugged, etc.)
Gaara is strong... but he's not kazekage in the manga yet... Gaara was beaten by Sasuke, (yes, without outside interference, Sasuke would have won the match in the Chuunin exam.) Naruto, and Kimimaro. (Kimi would have killed Gaara if it hadn't been for his disease... remember? that lunge was dangerously close to Gaara, and he had ran out of chakra.) Now, in the anime, Gaara's power went through the roof.... because Naruto couldn't even land a blow on Kimimaro... when Gaara got him several times... so Gaara is stronger than Naruto.
Shikamaru is only a tad stronger than Iruka... but his Shadow jutsu and intelligence would ensure a swift victory...
Leave them the same...