I just played Fiddlesticks myself after being tortured by him many times in the last couple of days and I felt disgusted at how easy it is to dominate and oppress the enemy team with his Q and E, it's just unfair and not fun even for the person playing him, unless you're a sadist. And there's absolutely no challenge in playing Fiddlesticks, 0. At least with Brand you need to be good at aiming and timing your Q and W, but Fiddle has 3 point click abilities + ult which at ~260 AP does around 1.7k total magic damage after the whole duration at only rank 2.
He has a point click Fear that lasts 2.25 seconds at maximum rank, a 1.25 second Silence, self-sustain and insane amounts of AOE damage over time magic damage.
I know he functions under different rules on the Summoner's Rift, but in ARAM he's absolutely unfair to play and should be disabled.