Mystic Shot does reasonably generally fairly low damage (Ezreal's kit is typically meant to hit a lot for smaller amounts of damage that add up to a kill). In game terms, he's putting out somewhere in the ballpark of 60-100 points of damage per hit, if he hits, when a low health character has about 620 health. There's also a few seconds wait before he can use it again.

The blink range on Arcane Shift is probably a few meters at most. This image is of a similar character who has a roughly equidistant blink, it looks to be about 3-4 meters.