I voted for Nocturne because, while I actually play him a decent amount, I hate the lack of subtlety in his kit. He is too much of a one-dimensional one-trick-pony dive bombing jump-scare when he could be a much more satisfying shadow-stalking incarnation of terror and dread. The description of how they plan to rework him seemed the best out of the options.
Volibear was my second pick.
I think Fiddlesticks needs something too, but the description on the poll didn't seem like the right vision for him in my opinion. I think that, yes, he should have more counterplay and more satisfying gameplay... but... "appearing out of nowhere" isn't the core of his identity for me, even though ambushing is part of his gameplay. I think his CC should be the focus of the rework and he should get a firm niche as a catcher class who can function well in the jungle role. I think some of his CC (probably his Q and maybe newly added CC) should scale with AP but his low-counterplay damage should be lowered. His E should be changed to do less damage when poking against active players in laning but somehow ramp-up if the enemy fails some sort of "counterplay test" like dodging it or stepping out of an area of effect. Jungle camps would be unable to pass the "counterplay test" vs his E, so it would still do plenty of damage to allow decent clear times. His W could also ramp-up in damage over time but start out weaker, which would allow good damage output vs monsters that don't attempt to break the tether. His R could empower his abilities while crows are flocked, turning his Q into an AOE around him and increasing his E size for examples, and the R could last longer (maybe scaling duration with AP) but do less damage per second. Overall, this kit would make Fiddlesticks rely more on CCing enemies in order to add reliability to his other abilities and give him time to deal damage. If his utility scales well with AP, then he will continue to build pretty squishy with AP as a catcher even without high damage AP scaling, but if he lacks utility AP scaling then people would play him as a tank which would not fit his visuals.