I totally agree about Harrelson being completely miscast. I always imagined Haymitch as being a fat, bald, sloppy drunk. Harrelson seemed much more like a functioning alcoholic who would look rather nice with a haircut, shave and shower. The Haymitch I imagine was well past being cleaned up. I don't even know if the book ever mentions him being bald or fat (or maybe they specifically mention him being lean and having long hair) but that is the image stuck in my mind.