Clearly Madara since he can use his Susano without any eyes. If that doesn't count then I would say Obito since he can spam Kamui every 5 minutes and hasn't shown any signs of losing sight.
Definitely Madara...then probably Sasuke due to EMS or Itachi. Obito has senju DNA which would have amplified his sharingan skills so I excluded him (even though Kamui is awesome). Plus he doesn't have susanoo/amaterasu.
I'm going with Itachi knowing that He used Sharingan in all the ways (genjutus, ninjutsu) while Maddy most of the time used only Susano and was more dedicated to Hashirama's wood and as for Sasuke -he isn't as good as itachi and was more dedicated to Lighting techs..
Obito enough said. He has the most powerful ms technique, he has shown to know izanagi, he can control the kyuubi with a 3 tomoe sharingan, and he never goes blind