Failry safe. As my self, new to this game, i find it pretty easy to execute it, while bringing enough dps for your team. Takes time to ramp up tho. Lack of lifesteal bothered me, theoretically Manticore should be better than Vampiric Assault. Still triyng out some new stuff, so i will keep you updated.

Usually this is the worst part of the game for Valla. Just try to contribue with as much exp as you can. Engage small skirmishes when you're in number advanatage or exp lead. Save your e for escape, using it offensive isn't recommended. Till level 10, you will most likely be outdueled by most heroes.

She is a beast in late game. Her constant high dps will melt anyone from their team. Just play it safe and choose your position wisely. In case an assasin jumps on you, use Blood for Blood and Strafe away from him. The combination of her AA with Rancor, Giant Killer will melt their tanks, making you prio target to focus. Also Vampiric Assault will keep you in team fights.

Valla excells at high persistent dps, while being fairly easy to play her. Only thing she lacks is mobility and weak early game. I will keep updating guide, so if you got any question, i will gladly answer all of them. In case some of you want to see some Valla action, you are free to join my stream:

http://www.twitch.tv/giglang

Hope this guide will help you.