Will - in the beginning, he was clearly the funniest, but as time went on he went from a kid who was trying (and failing) to fit in into the lame class-clown who always got all the chicks and became way too predictable
Seriously, anyone became way to predictable with the time. The Uncle is the fat one, Carton is small ..... always the same jokes.......but I still love it......in the end it was just way to predictable in my opinion.
My favorite was Will cus he was very consistent as someone earlier said... But Jazz had classic lines on that show... Especially the episode where he wants Will to have sex with his girlfriend so he can have a baby cus his little soldiers weren't working...