It used to be AoE before Morde's 5.16 rework.
But that was so long ago, I guess noone really took the time to change it and the wrong data just stayed there.
If you plan on buying champs with IP, then you should buy Jhin if you enjoy him.
I don't think there's any real way of making it work. LeBlanc's level 1 is horrible because she has no way of proccing her passive, and she's got the nasty combo of not dealing damage while taking a huge hit from a single jungle camp. Her first clear is simply terrible, and it puts her so far behind the enemy jungler that no build will ever be able to come back from that sort of disadvantage if the enemy jungler plays anything decent. On top of that, the meta right now favors junglers with a strong early game, that will surely have a lot more presence than you early game. Her ganks aren't anything to write home about considering you have to use W to even get in range, and land E to deal any sort of damage.
TL;DR: No matter the build, first clear is so bad you'll be behind all game long.
Fiddlesticks works a lot better in the jungle, because he can get consistent healing and damage out of Drain, while in the mid-lane, he has trouble landing reliable damage on his lane opponent or sustain properly, as Drain will kill minions in 3-4 ticks and champions will run away from him before that, without even accounting the mana issues he has, even in the jungle he needs his blue buff quite badly.
Fiddlesticks isn't very good in general this season, though.
In kill lanes, Kennen support can be a thing. I don't recommend it. Teemo is also frequently picked support in low elo. Again, I don't recommend it.
Apart from Lulu, the current yordles aren't good at supporting.