A) Is Vi fun to play against and play as?
I love playing as her playstyle and her personality is just awesome. Have done mostly pvp with her in top lane, usually building or trying to buid: Merc Treads, Frozen Mallet, Black Cleaver, Hydra, Iceborn Gauntlet, Spirit Visage.
Her Q having the charge up was interesting for non team fights it is a useful initiate if they dont see you coming as it telegraphs and is really easy to avoid, other than that I use it after initiating with ult to cc the enemy team
Her W I feel is starting to feel a bit out of place it had been the thing that tied her kit together and while the damage was initally way too high now it doesnt seem to accomplish the goal of tying it together.
Her E is great for poking champs through their minions from under your turret early game or just clearing a wave late game (or busting a turret without minions).
Her R is aweseome visually, although I do think it should still apply her w as she does pick them up and throw them in the ground.
B) Does Vi feel right when you play her?
Yes, with the exception of the removal of the w from her ult. Particulary since the w seems to have had its numbers changed as well
C) Is Vi someone you feel is worth bringing to a team?
Yes, she is capable of building moderately tanky and still has the kit to cause people to target her first, keeping her team alive.
If you have any feedback that doesn't fall under one of the above topics I'd still love to hear it.
My Suggestions for Her would be;
Q Stay as is,
W 6/7/8/9/10% +0.01ad scaling(think it has been set to this scaling already) or no scaling
e Stay as is
R Apply w to all units hit otherwise same