Fiddlesticks passive rework idea!

I've always thought it was cool that the 3 main champions that can use the fear cc on champions (excluding hecarim) are all "friends" according to the lore: Shaco, Nocturne, and Fiddlesticks.

What I find more interesting is that all 3 of those champions inflict ACTUAL fear into the enemy team. Example: That gut wrenching feel when you're already locked in as jungler and the enemy team locks in Shaco after you. Or how all enemy laners move closer to their turret when Nocturne ults (actual paranoia). And how the enemy team is always keeping the jungle warded in fear of Fiddlesticks' ult...

But they aren't.

Fiddlesticks is the laughing stock among the 3. Yes his ult is powerful but he's just not... scary

Maybe I'm just not as experienced to recognize his true strength. But this is the idea I had:

Add a new passive to his ult. Whenever Fiddlesticks moves around and is unseen by the enemy he gains stacks slowly. Being visible to the enemy team makes these stacks decay at a faster rate than they build up. At 100 stacks crows swarm around him (visual thing), whenever he ults his crowstorm will have a red hue (and the cawing sound is louder preferably). Additionally, his ult shreds % magic resist to anyone in the area each tick as well as slows enemies for 40/50/60% (per level). I'm not the kind of person to run a bunch of calculations to post an idea so I didn't put a number for the actual % magic resist shred. As a bonus his passive can be used for ward stomping but if that's too much then things would have to change.

So really it's just a passive added to his ult, not really a change to his passive (which is still pretty boring).