In the manga when he meets Rin after he died, he appeared in his child form before her.
Now, I'm not against this from a technical perspective, but one about character portrayal. I feel it could have been a much more memorable scene if Obito appeared in his scarred, adult form, just to emphasize how much he had been through in life, and how Rin's spirit would be compassionate and soothing, would understand and accept him anyway, regardless of his flaws.
Thoughts?