Nidalee's Q should have an indicator enemies can see just like Jinx's W

Or they could make it one of the slowest moving and obvious looking projectiles with a small width.

Jinx's Zap! has an indicator because it is really freakin' fast once it goes out. This is beside the fact that it has a cast time, and the indicator line shows during the cast, not after. When exactly would Javelin's indicator show?

But seriously, thing is so easy to dodge. Like really, with 300 ms it should take you no more than half a second to move out of the way, and it's slow as heck.