Tell you what. Buff her Jungle presence, and I'd accept a Top AD Nidalee nerf, because her kit wasn't designed for Top AD, but suffers hard at jungle atm.
She's pretty much the only jungler who has a messy as hell early game, and find it very hard to stay up in health pre level 3. Post level 3, She still takes so much damage it's hard to reliably call her a top tier jungler.
She's also one of the only junglers who still follows the rule: I only exist in one part of the game. If your team doesn't respond to ganks by Nidalee early game, you're more or less finished. Even if you go 16/0 early game, you're finished if you don't end the game by 22-23 minutes, because after that, you just become team fight fodder.
As an AP "Assassin" as you call it.... she has a less than 50% win rate. Kill averages are low, deaths are high, assists are low.
She again is using 
like 
, because while her clear might be fine early, it's usually taken late, falls behind often because ganks are unreliable, and has very small windows to do anything late game when not played as an AD top.
Any jungle mage that needs to rely on a Frostfang tier has serious issues. It means either the jungle has been undertuned, or that AP junglers are nerfed hard already.
Personally, I feel like E doesn't even heal anymore. I can have 300 AP, and it heals me for 220 HP and I think...... wtf is this for anymore? Healing in jungle farm basically results in a situation where you are clearing 3 camps on less than 15% HP, making a real juicy target for an invade.
Furthermore, what I find funny is, her current winning runes have nothing to do with following up a hit spear. Like with It's all about Electrocute dealing too much burst. Nidalee's kit reeks of being good with Phase rush, yet somehow Electrocute stomps it out.
Late game I can have 700 AP on Nidalee and an almost full range spear often only hits for 30% hp...... i mean wtf needs nerfed about that? Normally, if I try to go in and land the kill, I'm going to die, because my target's team has knockups/knockbacks.
Personally I haven't played Nidalee since early Season 7 until recently, so I'm not perfect. But I can see inherent flaws that didn't exist which make her easily the most miserable jungler now. If I play Norms game with NIdalee, I just want to slit my wrists. Gank bot after pinging 20 times, am behind ez/thresh just waiting for 8 full seconds for my team to move, and they afk farm! Go top, try to gank Fiora for Nasus. Nasus doesn't move, and just says "don't need help. Leave" Wtf is Nidalee if not a "MUST GANK LANES" jungler?
can clear faster than her, safer. with more hp.. and without needing to worry about an invade. and still have hp to gank afterwards.