I think that Nid is one of the best champs in the game for skirmishes and picks, in and out of the jungle. High mobility, scouting tools, long range damage and short ranged burst make her a true bestial huntress in small fights. Which I think is awesome and fits her theme perfectly.
However, she can't teamfight for shit. I mean really. Her whole assassination relies on hitting a spear, and the chances of hitting a priority target with a spear while they're grouped with their team is close to none. Essentially all she adds is some attack speed to her ADC (which is very nice actually) and maybe chunks a tank.
This isn't always the case when she flanks or "cleans up" and this is what she has to do in order to really do anything, essentially leaving her team to 4v5 while she waits for people to die out.
She rules the early-mid game when full 4-5 man fights aren't really a thing, but falls off hard whenever the enemy team decides to group.
She split pushes much weaker than something like a zed as her 1v1 potential is reliant completely on hitting a skinny slow moving skill shot.
Honestly I think Nidalee is pretty ok where she is. She has one stage and role of very high-effectiveness and other stages of utter uselessness. Counterplay is more at the macro level than the micro level.
HOWEVER, that being said, I could support some nerfs to her early clear speed, as hitting the fast level 3 and then pouncing to the enemies second buff while they're still trying to complete it is sorta dumb.