The hair color should have been either like this :
Or like this :
I think these softer shades of blue are easier on the eyes and work even better than what we got.
Now here's how SSJB should look like without the aura on :
Silver blue instead of turquoise, just like Toriyama imagined it.
Obviously that's totally subjective, it's just my personal view on how they should have done it. Feel free to give yours.