As someone that truly loves Community I have several things I HATE about it.
Chang has been HORRIBLE and I repeat HORRIBLE since after Season 1. He shined so brightly as Professor Chang and was awesome. But then they changed it all around and every season he's something new that's not funny.
And on a broad level, Community has gotten way way too bizarre and into another dimension at times. This is NOT some Sci-Fi show and to put surreal stuff in it is not good for it's true purpose. You can be wacky, silly and all that but this timeline jazz is a ruination of the show.
After Season 1 I wanted them to get out of the college some but they've gone so over the top. Too many episodes are not resembling anything of Community's real plot line which is classes and studying at Greendale along with other school activities.