Hey everyone,
this are my first two builds for Sylvanas.

Main talents
Wailing Arrow is in my opionion the absolutly better choice. You have a greate AE-damage (,which gets pushed by Deafening Blast) and has additional 2.5sec silence, which is extrem powerfull to enter teamfights. The only disadvantage comes with enemy stuns. If you get stunned after releasing the shot, you will not be able to use it correctly and it will be failed.
Life Drain & Lost Soul are extrem powerfull for farming and healing up any camp- or snowballdamage. A possible alternative for Life Drain is Unstable Poison, which grants you more farming possibilitys for the prize of no option to heal your self.

"Dps focused" build
In my "Dps focused" build, I focused on a higher burst with Withering Fire. I pushed the number of
Withering Fire shots with Ranger's Ambush and in combination with Splinter Shot. With this two talents you create shortly up to 20 Withering Fire shots in endgame.
A additional boost is Cold Embrace, which should be more often ready because of Lost Soul.
With this build should it be possible to farm camps and minions as also do a lot of herodamage too.

"Farming focused" build
My "Farming focused" build is focused on avoiding campdamage through Paralysis. With this build
it should be much easier to farm camps. Also does Overwhelming Affliction a great job by chasing enemys and should be a good combination with Paralysis.

"But which build is the better one?"
"Farming focused" build seems to be the better build. Sylvanas isn't created to be a assassin and so on she needs no higher herodamage. The main aspect of Sylvanas is to clear camps and minionwaves without any problems on your own. You have also the role to support your team with silence and slow. This is more helpfull like trying to get the damage of a assassin (Btw. yes, currently you can do a lot of damage with the "Dps focused" build, but this isn't your role and you will still do enough damage without this talents).