In my opinion, there are many things that Kishi could do with the Kamui dimension issue. I will least them, and give my opinion about each one of them:
1. Obito can have an extra boost and save Sakura while dying
Well, this is a possibility, but it would be BS because Obito already said that he cannot control black Zetsu anymore. however, since we are talking about Obito, anything can happen. Maybe, he can pull a last Rin moment and go god mode. If that happens, it would actually give him a heroic death, but pitiful as he would die alone in his dimension - no friend with him.
2. Sakura goes god mode
Above, I stated that while Kishi cool make Obito phase Sakura in the real world while dying, it would be a pitiful death. Thus, another possibility is for Kishi to show that Sakura can pull some serious moment for her fans. It would be utter BS, but who care about that. Why would Sasuke get all Kabuto's meat without any effort, and deny Sakura a new beautiful face with a Sharingan and Rinnegan?
Zehahahahahahahahahaha...haha.
3. Sasuke shifts in the Kamui dimension
This is also a possibility since I know none of his fanboys will complain. They would all be like- Sasuke is badass. With the uchihatard, you don't need reason, you simply tune in and accept anything.
However, since I am a conservator, I think this is BS. thus, we need a more acceptable situation.
4. Madara only wants his Rinnegan
Yeah, you heard me. The stupidDara could just take his eyes, mock Obito, and leave the Kamui dimension. It would not be the first time he would do such thing. See, Madara does not care about who is reading the manga. Rather, he troll every single prediction about him. Well, this would be another great villain fail.
So ....
5. Tobirama created it, Minato took it to another level, and ...
I am fired up to see naruto take FTG to a final version. If you remember, Minato spoke of Hiraishin level 2. This means there are different level for this jutsu, and I believe that just like Ashura, Naruto will tap into both his parent feats very soon. We have seen him using all the KKG, meaning in matter of Ninjutsu understanding, he has passed the roof.
So, a very good way for Kishi to introduce naruto's FTG would be now - that is go to the Kamui dimension to save his friend after Obito loses the Rinnegan. How will this be possible:
Well, we know that Naruto's chakra is within Sakura from previous connection. We know that even a trace is enough to replenish it, and we know that Minato could teleport to anything that has his chakra, and he can also teleport anything that has his chakra. So, Naruto could just teleport Sakura, or teleport to her.
I think the last choice is better since I don't want Obito to die alone.
