I'm with Mitros again. We were there the first week of F&WF about 3-4 years ago. It was a nightmare. It was wall to wall bodies. I don't know what 'crowd levels' people here are comparing them to, but it certainly wasn't the Sept crowds I had expected, and it positively was NOT the crowd levels we have experienced every Sept SINCE then. (Ever since then we have been sure to book early Sept). There are other things to consider as well. Lets just say if you like to like to drink and party it's a great week. If you don't... you might want to change your plans.
Epcot is my single favorite park. We have watched Illuminations (added it up last trip) almost 100 times.

If we spend 8 days on Disney property we spend 5 of them in Epcot. The first week of F&WF was NOT the Epcot I love.
It's completely possible that we just had a bad week and a bad set of circumstances, and it's VERY possible that you would have a blast. But you asked, so thats my opinion. I won't do it again.
With that being said I agree that it gets worse towards the evenings, but that's my favorite time in Epcot.