I'm thinking of buying Neeko because her Passive seems cool, but I'm not a midlaner, and her primary abilities don't seem that special. Is she fun to play, and how useful is her Passive?
Can she be used in other lanes, and is it practical to do so? Mid is the one lane I really can't play. 
The 3D rigging on her lizard tail is also cool. :) But that's neither here or there.
Nobody can actually answer that question for you because a champion "worth playing" is entirely determined by if you enjoy playing them.
Oooh you're a Syndra/Lissandra main. How neat!
I'm wary of her being nerfed later since she's a newer champ, but it doesn't seem like she's causing as much of a stir as Kai'Sa or Pyke did when they were introduced to the champ pool.
I main support with my primary janna, soraka for years.. I love neeko's kits, have found success in every role with her. Changing up builds to match role and opponents takes a bit to learn.
But if you like trying to mess with people's heads then I'd say yes learn the ways of neeko! I've been able too pull off crazy jukes with the w - throwing myself at the enemy just too run away behind them xD.
I got her, didnt do too well on her my first time. Played against her, got rekt gg. Her team fight is insane with her ult and she can pull some crazy stuns off. Lots of cc with great dmg.
Neeko can actually play any role. Try playing her as an adc and build 
. It's actually quite monstrous, and does better as an adc than trying to play an adc when you do not know the role as a crit build of some sort. You just need to learn the right build for each role.
Thanks for the advice! All good stuff.
she doesnt do quite well in this meta RN but shes pretty good for counter picks!
