@Riot, Are there any plans to do anything with Fiddlesticks?
Fiddle has always been a decent to strong pick since at least I've been playing, that was until the Magus/Runeglaive changes. He REALLY got hit hard from the jungle item changes. 10% loss of CD reduction, loss of AP, and a relatively useless sheen proc. And that wouldn't have been nearly as bad if he hadn't got nerfed time after time (deservedly with the items he had at the time). He just seems really clunky to use now, with no real clear way to play him.
Whether it's the fact that there's really no good jungle item for him, you can't cancel your ult upon re-casting it (something like Pantheon would be great), ect, it just sort of feels like you left him there with no clear ideas for him.
Much like Sejuani, you nerfed him, than the item he used as a core build, then never did anything to make up for the massive changes to his kit. It's clearly showing with his pick rate and win rate now. Sitting at a little over 2% pick rate and under a 50% winrate, he obviously needs a bit of attention.
Ideally it would be as simply as adding a Magus like item back into the game for AP junglers that don't benefit from the sheen proc. Personally I don't see an issue here as AD junglers get 2, potentially three options depending on the champ. But doing some basic changes like being able to cancel his ult for a significant CD reduction, or maybe upping his fear duration would help him quite a lot. Any insight would be helpful as he was quite a fun champion to play, but now seems kind of all over the place with no real direction.

first, they still ended up buying magus as a 2nd item. The jungle items are very cost efficient. Buying runeglaive is almost a waste of gold now since the proc doesn't help him.