P.S. As much as I would love for Naruto to get Rinnegan, i don't see it happening.
Naruto and Sasuke are an allegory to the original two sons of the Rikudou Sennin and we should remember that it was the Uchiha brother who thought true power was in the eyes and the Senju who thought it was in love. Since Naruto represents the Senju brother I don't see it likely for him to get power of the eyes. I think it MUCH more likely for Sasuke to awaken the Rinnegan instead.
There are a couple of arguments against that though:
1. Sasuke is extremely Pro-Uchiha so him taking Senju DNA is very not like Sasuke.
2. If Sasuke were to take Hashi's DNA (The only remaining Senju DNA that is plausible to use) the fight would be absolutely pointless. Sasuke with EMS, Mokuton and Rinnegan? So basically a living Edo Madara.
3. Naruto is an Uzumaki, not a senju. So the argument that he represents the younger and Sasuke represents the Older is pointless, since Naruto is the only one who actually wants peace.
4. It isn't clear how the Sage got the Rinnegan. The Rinnegan gives control over the Juubi so the Sage should of just controlled it then right? Wrong. If he had it, he would. More facts point to the Sage getting the Rinnegan because of the Juubi's internal influence.
5. So by this logic, Naruto who has the power of 7 Bijuu's bestowed upon him, already has near suitable pre-requisites for the Rinnegan. Also, more facts point to the Sage being an Uzumaki.
6. It wouldn't make sense for Sasuke getting the Rinnegan because his chakra reserves are nowhere near Naruto's, who's chakra reserves are near perfect for the Rinnegan.
I could go on but... Yea you get my point.
Thanks for your input though! I appreciate it!