Now it's no big secret i'm a newb and i suck. Unless it's Morgana. I usually wreck faces with her. But when i look at Vi...i just feel this is a poorly designed champ. The current Vi can be either:
a) kamikaze - rush/ult into them get killed hoping you killed your target before their team wreck you
b) "pursuer" - rush into them then they run...and you got no slow until you itemize for it. So you chase. And chase, and they run, and ...actually it ended far sooner cause they're already under their tower.
When i play Morgana i feel everything in her kit makes sense and synergizes with eachother. But with Vi i feel the idea is "get to them fast and then...yyy...ee....ah nvm, player's will think of something!"