Accelerated depletion of chakra is the trade-off for the visual acuity and copycat perks of the Sharingan. Heightened performances in combat are what compensate for these risks that are undertaken. The eye is no longer a burden to him - as a consequence, his stamina is more preservable - but Kakashi was never been known for his endurance. In fact, his stamina only ranks at a standard 3. There's always room for improvement and I'm confident that he's managed to train his body to persist longer, although I don't believe his chakra stats are going to skyrocket to a perfect 5.
That's a very good point. You're right. The eye was also a burden, so there should be some advantages in losing it.
Losing his keepsake could incentivise Kakashi to redouble training to make up the difference. I agree that's he lost his S-rank status, but with enough effort, he might be able to reclaim the ground lost using his base skillset. Most of the Akatsuki and the Kages would be too much, but I'm thinking that he might stand a chance against some of the weaker members like Black Zetsu, Hiruzen, and Mei. I would like to suggest Kakuzu as well, but his heavy usage of those tendril appendages and the five elements could make him too difficult to beat.
How will Kakashi fight against Mei if he doesn't have the Susanoo to protect him from the lava or acid? Granted, his Taijutsu are probably better than her but my concern is how will he able to get close to her? Seeing how Mei herself wasn't affected by the acid in a closed room setting (against Sasuke), she could surround the atmosphere around her in acid without hurting herself. Probably Kakashi can attack from underground, but Mei is an earth type too so that's not plausible. None of Kakashi's elemental ninjutsu would be strong enough to counter her kekkei genkai ninjutsu. The unknown factor is genjutsu.
And Regarding Hiruzen, I agree Kakashi could win with Taijutsu due to Hiruzen's old age and Kakashi being more faster, agile, and flexible because of that. However, it's essential that he beats him up before Hiruzen summons the monkey king. Taijutsu would not be good enough when there's a monkey king who defeated the strongest Kage in hand to hand combat (Hashirama and Tobirama).
Edited by ramenanmitsu, 04 September 2014 - 05:18 PM.