He's like any of the creative minds. You either love him ,or hate him.
To his name tho, He helped write one of the most popular 3d animated films of all time.
Created 2 Successful TV series/ IPs, 2 other TV series that have insane cult followings, and conventions devoted to them.
One of the most popular web series on the internet.
O and a hit comic series
And we will see how the Avengers does, but I'm pretty sure it will do fine =P
Pretty good career imho