Question.

[Drake]

Rad's hair wouldn't grow because the whol growing of hair in Goku's case was probably his body adding new mass to contain the enormas amount of energy that Goku was out putting.

SSJ3 is ridiculsously strong, it penetrates the upper levels of dimensions. Even though Gohan, and Kaioshin were in another dimension all together on Kaioshin-kai, they could both feel Goku's power.

Not only that but Goku had enough energy to stay on earth for a day, and using SSJ2 didn't seem to drain it that much but when he went SSJ3 it went from like half a day to 30 minutes.

EDIT: I CNA GO SSJ2!!1