What is Minato doing with Madara and Hashirama option? Minato is akin to a spec of dirt stuck under their shoes. Please stop over-rating this guy. Also, according to Kakashi, Obito's S/T jutsu meaning Kamui/Intangibility is better than Minato's FTG. Are you people still stuck with that lucky win Minato had against a 14-15 year old kid, who was also controlling Kurama? Give me a break.
As for the question, then Obito is definitely one of the most powerful ninjas in the entire Narutoverse. I believe only EMS Madara and Hashirama top him.