Madara gradually ramped up his powers as he was wearing down the Kage - toying with them, actually. Again, total arrogance on his part - but from a strategic standpoint, brilliant. Problem is Madara knows THAT, too. What I want to know more about is the body (plant, more likely) that's walking around and calls himself Tobi and the relationship, for lack of a better word, to the soon-to-be-corpse/edo tensei puppet Madara. My guess is that Tobi is a perfected plant "puppet" on the order of the "puppet" Sasori. That part has always been hazy. I hope that gets clarified so all this Tobi is Madara is Jesus Christ discussion ends (I'm not a big fan of arrogant type characters; I'm more into underdogs).
As far as Sasuke goes, he's hopeless. Like I said, he never got past the "Konoha hurt my big brother" issue. He's going to continue to slink around for a while. Kishi's going to kick him around a bit for the emo factor and the buildup to a battle with Naruto, which will probably take about as long as this edo tensei did.
I think one of the several shining stars in this edo tensei arc - and this manga - is Itachi. He got his unresolved issues handled so he will no longer be bound to the "imperfect world." It's sad to see him go but he's going to go out the way he wants to: buried in the shadows with no recognition except by those that count the most in his mind, namely, Naruto (Yes, he. loves his brother but I think he most identifies with Naruto now due to similar ideals).
I say we leave Karin in a straight-jacket kissing a hand drawing of Sasuke while the other two, Jugo and Suigetsu go out and pillage and plunder in the manga. Those two make quite a pair.
Ok, one out of left field question: what on earth was Dan's jutsu that was so disastrous that he had to be placed in a jutsu right away? We'll never know now at this rate. I wonder how many other "stragglers" Kishi left in the "unknown" or "unnecessary" column...