The only bike I own that I would consider powder coating someday is my 1988 Cimarron. Its not worth the expense financially. But it continues to be my main go to bike, and it had paint as bad as your Stumpjumper when I got it.
I touched it up at the time, its OK from ten feet away and is working. But cosmetically, touching up that much paint damage will never look good at least at my skill level.