I completely agree. Sasuke is a lot stronger now and he has had time to train and get used to his new eyes and improve all of his jutsu. Even in the first panel that we see of him emerging during the war, you can clearly see thunder and lightning going off in the background.
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It seems to me like Sasuke was messing with the clouds and perhaps making some advancements on his Kirin just before emerged to take part in the war.
The natural energy is what makes Senjutsu effective against Obito. Although Kirin isn't senjutsu, it is still most likely an effective jutsu to use on Obito. Although, since Black and White Zetsu have already seen Kirin, Obito probably knows about Kirin already, so it'll be interesting to see how Sasuke tries to pull it off.
Either way, OP is right on with everything. I don't know why it's so hard to explain this to people... They think that just because Kirin isn't Senjutsu, it's fodder against Obito, although its the natural energy that helped Naruto's rasengan hurt Obito. And honestly, if Sasuke doesnt have Kirin then what else can he use against Obito? Nothing, he'd just sit there with his Susano holding his d*ck, and that wouldn't be good for the story. Kirin, on the other hand, would be.
EDIT: I'm not a Sasuke fanboy by any means. I'm about as far from an Uchiha fan as one can get, but it's obvious even to me that Kirin is on its way. Maybe Naruto and Sasuke can combine their natural energy attacks too :3