Evelynn needs MS on her Passive or her Q needs a LOT more Range when her Passive is on.

I pretty much have to Flash ---> Q right now to get off a Charm unless the player is ridiculously overextended.

As a point of reference, Elise's Cocoon, which is very similar in terms of missile speed and width, has 1075 Range. This is 275 (34.4%) LONGER than Evelynn's Q. Hell, both abilities have the same CC duration at Rank 5 in spite of the fact that Evelynn's kit is far more binary to begin with.

Throw in a partial (ideally 50%) reset on Evelynn's R (or maybe 30% per enemy champion killed within a few seconds of her hitting them) and Evelynn suddenly has far more depth and effectiveness in her kit.