i dont think so, because the rinnegan is a evolution from the sharingan.
the only thing that makes him stronger through this is the fact that he have kamui.
Well, he doesn't have Susanoo or his second MS ability, that's the advantage of having two MS's.
And I'm pretty sure there's another advantage for having both Rinnegan eyes.
Yep. Reason, I assume, why Kish has not given him an advantage by using both Doujutsu in battle. In my opinion, he could be equal to Madara, if not, as close to equal.
thats actually a question ive been wondering, i think 2 rinnegan is stronger or more powerful but having a MS gives you that ability which is exclusive to the wielder
I personally believe someone with both Rinnegan (e.g. Pein) would be stronger, or Obito himself if he had both his Original MS.
He has only used the Rinnegan for his paths which have disappeared now, so currently his Rinnegan is redundant.