Like I said once I do not care if sasuke gets the renenngan hell I hope tobi is the devil that way we get a fair fight against naruto I mean they were times when even luffy had to run,natsu admit defeat etc but in naruto that does not happen he defeats u there on the spot no matter how powerful and regarding the scroll I think it has info about tobi on it info tobi wondered how kabuto had them info about his real identity and plan
n1. one comma. looks funny ;-) and makes your post more easy to read/understand :-D
to topic:
normally i wud say, i kinda dislike sasuke. bcoz imo he mostly got his "powerups"
to easy. or coz at some point he somehow starts acting weird an irrational.
sure, for a badass-avenger it could be symptomatic, but me still doesn't like it.
the chapter though, i like better.
despite the flashbacks and stuff, imo the plot's evolved a little, and some of the "facts" we thought we know are dragged in doubt again

and btw. i don't think the uchiha-brothers will have a second clash anytime soon. ppl already mentioned that itachi will probably handle kabuto.
and i think sasuke's drop-site will be between the tobi vs naruto folks.
but i assume naruto and sasuke will just get a short glimpse at each other (perhaps even at their actual skill-level/skills) before they get divided by the tide of battle (that point i will have figured out by kishi himself, he's a little better in such things than me :-D ) (we still don't like the manga ending too soon, do we? ;-) )
and for the "weak" sasuke using susanoo and stuff for this bunch of zetsus.
i don't think he wasted chakra or he showed off in some sense.
correct me, but i remember that was the first encounter, after sasuke got his brothers eyes implanted. i would try them out 4 sure as well. :-D
so i would say, he did not show his full potential/power, but he used "new" skills just to try them out, and that is why it might have looked like he uses a gun three sizes or more to big for the group of white weaklings.