I was wondering about the similarities that Obito has to Darth Vader, but I don't think Kishi simply copied the concept of Star Wars. Those themes have been existent long before the creation of Star Wars but thanks to it's huge popularity is seems most people like to associate it to those movies.
Obito, and Vader in the last film, are being portrayed to be tragic heros. The reason Obito gets so much hate, at least in the west, is because of people's tendency to be extremely critical of how characters are developed. It's the same situation that happens with Sakura. But I'll be clear, being critical is not a bad thing, it opens the doors to further discussion so I'm definitely not putting down people's opinions.
Putting extended criticism aside for a minute, when one thinks about it Obito was meant to be a character to be pitied on because he was the victim of circumstances beyond his control (Rin's death). It's the same sympathy people might've felt for Vader in the Return of the Jedi now that people knew he was previously a force of good who simply went wrong thanks to fate.
Obito is doing evil because of his desire to see Rin again and change the world's fate. Anakin got tempted by the dark side for his desire to change save Padme's life, therefore changing her fate. Again, we can argue for hours about the justification of their actions given the circumstances but that's not the point. The point is that both got dealt a bad cards in life.
Now Anakin finally found redemption by saving Luke, his son, which in turn finally allowed him to change fate. While he couldn't prevent the death of his wife he was able to save his son from suffering the same destiny. I don't know how many other stories have this same redemption concept but I believe is a standard created many centuries ago that Star Wars was simply inspired to use.
Given all that I've said I do believe that Obito is meant to finally have the change of redemption by saving someone's life. I'm not entirely sure as to who it might be but my gut is really telling me it'll probably be Sakura. I've mentioned in previous posts how I believe that Obito will come full circle by saving Sakura's life (which is this generation's Rin, that's too obvious).
It's a sort of lost life saved life kind of deal, it's a way to establish balance. A life is lost and then all goes to hell, then a life is saved and order is restored. There's also a connection with the life that is lost and the one that is saved. With Star Wars the connection is that Padme and Luke are Vader's family. With Naruto the connection comes from the parallel of their roles (the medic ninja that supports the hero while he loves her, yet she loves the rival).
We can also mention how both Obito and Anakin where influenced by a greater force of evil in the shape of Madara and Palpatine, and such manipulation is what lead them to take on their alter egos of Tobi and Vader. Also, they had a tendency to wear masks.
Vader saved Luke, who was an extension Padme, from Palpatine. That changed the dark fate that was established with Padme's death. And so I believe Obito will save Sakura, who is a reminder of Rin, from Madare. That will change the dark fate that was established with Rin's death. And as one might expect saving that life will cause the ultimate death of the tragic hero, who will die glad to have finally changed the course of destiny.
As for Madara dying by Obito's hand like it happened with Palpatine by Vader, well, I don't see any reactors around the battlefield to throw Madara in so I guess that reduces the chances.

In all seriousness I do think instead of killing Madara that Obito will leave him in some sort of disadvantage as he dies.