So, several things here.
• Senjutsu vs. Ninjutsu is interesting as it's essentially "natural magic" vs. "artificial magic" makes it interesting for how his powers only directly nullify and counter the one source. I really like the idea that he can counteract Ninjutsu because the Sage essentially created Ninjutsu abilities, but Senjutsu is still effective because it existed even before he did, since it's natural energy.
• I'm wondering if Juugo will be involved at any point, since that's where his abilities stem from, and they could make him a really useful asset.
• That moment when you realize that Kabuto having Sage Mode was probably because he knew about this and made sure to obtain that capability as a contingency plan, so that at every stage of Madara's plan, he's still a legitimate threat to them if they attempted to turn against him.
• Additionally, since it's been established that the Toads & Snakes are both capable of teaching their human disciples Senjutsu, I'm curious whether or not Sasuke's next more will involve summoning a Snake, since he can't use Senjutsu on his own, but his experience with fighting Kabuto plus seeing the Toad/Naruto use those techniques should tip him off to that ability.
• Furthermore, I'm wondering if summoning contracts might end up being more utilized by some of the non-main / non-crazy elite characters as a way to contribute to this battle.
It's clear why Madara wants to engage Hashirama directly while he's at his peak, since Obito can straight out kill him, and he obviously wants to be the one to do that. His powers are now sufficiently non-Bleach-like which is nice, but it'll be interesting to see if he maintains his combat form as a sort of super-PTS-Gaara, or if he eventually starts to control some of the Six Paths abilities more like Nagato.
It's nice seeing how Naruto's scatterbrained yet observant attitude comes from his dad, and how much they think alike when viewing opponents that they identify with. It's interesting how much more you see of his parents in him the more we've gotten to interact with both of them. It's especially cool seeing Tobirama as a secondary mentor who can understand Naruto by comparing him to his dad, and being able to read them and coordinate attacks with them so well. The man would've been a HELL of a Hokage, and his radically different attitude makes me really curious about what his time in that role would have been like.
Lastly. OH MAN. KURAMA'S YIN SIDE.
I seriously can't wait to see how that pans out, because with the idea that he's mortal even as an Edo Tensei, it'll be really interesting to see how and when he plans on getting it to Naruto, and what the effect of that will be.
Tangentially related:
It'd be really interesting to see Naruto/Hinata & Sasuke/Sakura training together (for reasons other than pairing). Hinata's Doujutsu capabilities would be able to assist Naruto in controlling Kurama's Yin Chakra and balancing it, whereas Sakura would be able to assist Sasuke in recovering from the physically debilitating techniques that he uses.
Overall - EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE!!!!!
X 
Like how he/it doesn't sound that happy that Naruto figured out that the Bijuu are people too.