didnt itachi become anbu leader at 14? so its impossible that he killed his clan when he was 12.

other than that you're probably right about the akatsuki, if these guys are at itachis level. if all of the rest are like kisame it will be much easier for konoha to take them out, kisame had trouble with kakashi who is indeed a powerful ninja but there are more at his level. bring out tsunade, jiraiya and some high jounins and this fight isnt as easy anymore.