Need help with dps

[tykop 0]

Recently rerolled into an shadow priest and iam doing low dps and getting bad parses. Could someone help me with this problem?

Here is my armory: https://worldofwarcraft.com/en-gb/character/draenor/uulwi

And here are heroic and mythic logs: https://www.warcraftlogs.com/reports/PfV1QNHKR3BGmyC6#source=16&fight=2  &  https://www.warcraftlogs.com/reports/a2C7WDkA6RqTBxjv#source=3&fight=2 

I wanted to leave Mythic today because i was not doing too good so i only killed Goroth , DI & Harjatan.

[Yelaria 2]

Hi Tykop.

(I look at your logs from the heroic run. the mythic logs are privat.)

there are some points that you should really improve.

1st. You dont have the 4-piece bonus of the T-set which gave you a massive boost for your Voidform and your DPS. Try to get it soon as you can.

2nd: Your Gear: Dont look for the highest gearscore at your items. The secondary stats are so important for a SPriest and his DPS.
You have to much versatility (over 4,5k rating). Even with Spectral Thurible it shouldn´t be higher than 2k (3k with arcanocrystal as 2nd). 
These 2,5k rating should be at your crit rating, which also improves your Voidform (through "Unleash the Shadows and Auspicious Spirits.).
The weighting of the stats are: 1,8 - Haste . 1,51 - Crit . 1,13 - Mastery . 1,13 - Versatility . 1 - Intellect 
Use this to calculate new items and dont be afraid to go down with your GS when you can improve your stat-weight.

3rd. Rotation, respectively your cooldown useage. You use your Mindbender to late. The Voidform runs out while he is still active. 
Try to time it that your Voidform runs out 0-2 seconds after he disappear. (approx 25 stacks of VF / 30 with 4piece )

Ps: i also watch to your 2nd SPriest in the Raid and there are amlost the same problems with stats and mindbender.
Mabye you could show hin this Post =).