Just wondering if I could get some thoughts/tips on running Fiddlesticks support.
Be really careful with Dark Wind and talk to your marksman about what they want to do with their wave, as auto-pushing a wave because you want to harass can mess up the beat your ally is trying to CS to and through off their tempo.
Usually worth stealing 1 CS if you can get 3 bounces on the same guy by hitting 1 remaining minion, not worth if you through off the tempo for 3 CS and miss your opponents.
Also: you might want to try full-tank scarecrow.
Fiddlestick's base damages are absurdly high (if he can stick around long enough to use them), as his QWER combo is capable of ~2,900 damage with 3 bounces/max-drain/max ult. Average HP @18 is only ~2000, and marksman will have ~1800 more often than not. Even with 30 MR the effective hit points of a squishy is low enough a perfect combo will kill them.
While you probably won't get a perfect combo off and you're lack of levels will prevent a true OHKO blast, being able to stick around, absorb focus, and waddle in the midst of your opponents while you drain/fear spam is going to net you some solid presence and damage.
Also: Relic Shield kind of solves some issues with Dark Wind eating CS. Despite being ranged and lacking execute damage, it's not like Fiddle has issues finishing off the occasional minion.
I say this mostly because even with how solid support income is now, running spooky ghosts first will make you pretty squish for the majority of the game regardless of what you grab afterwards.