Dunno. She's definitely easier to survive with, no doubt, at least in my experience. I ended up going 6-4 with her today. 4-0 on my alt and 2-4 on my main.
5 or 6 of those we had no Tassadar versus them having a Tassadar, which made things a bit rough. Heroes like KT (bomb spreading), Abathur (mines), and really anyone with an AOE make it more difficult for you to get any kind of good opener reliably.
Man, there was some massive feeding from other Valeera's. I averaged 2.1 deaths and my opponents averaged 5.9 deaths per game. We faced two who died 10 times, two who died 8 times, and two who died 7 times. Actually, we only had 3 games where the enemy Valeera died 5 times or less.
The silence build is pretty good. I feel like her level 7 talents suck, but maybe I'm missing something. I can't tell if I like the regen globe talent at 1 or Subtlety. If I had one complaint it would be that her heroics are pretty god damn lackluster.