I am really like your build, one thing that bothers me though.
Please remove all the red spot-putty off the roof of the car and any where else you have put any of it.
Spot putty is just thick primer and keeps shrinking, it will continue to shrink after you paint the car, just giving you a heads up so you dont have to re-do the paint in the future.
To fill minor imprefections / pitting, just use reqular bondo.