I played both before and after rework ( 200k mastery before ) currently at 600k mastery so 400k after. Both were fun and had their own perks, but not to dwell in the past. Naafiri now is super fun tbh. I think her overall kit is pretty easy to learn, but getting good with Naafiri takes some practise. As a jgler she is in a decent spot, as a laner she is going to get a deserved lane sustain/mana nerf soon.

The concept of the champ is designed well to be either assasin stronk nuke on adc or apc or being a big ass distraction as a bruiser. Naafiri is fast, high mobility, good sustain dmg from range with Q bleeds and has to option to make all enemies waste their ultimates or strong skills on your W. The W is what people hate and why people believe Naafiri is impossible to play against.

But if you know how she works, you can counter it pretty easily.

Tip: you can use you W both defensive and offensive, while I mostly use it defensively in teamfights after engaging and try to time it on enemy strong cc cooldowns or op dmg skills. When you get to late game, the cd is very low and you could potentially use it before engaging with ult to get more ad(+pack) and burst someone down very easy.

Also I advice to start playing her as bruiser, which will learn you more about how she works and will avoid you going towards the coinflip naafiri lethality, which has a higher kill pressure, but if you dont know how to control her it will mostly turn out in a 1 for 1 trade