With 7.1.5 comes a change to secondary stats, basically what they’re doing is increasing the amount of stats you need to gain 1% of that stat. Blizzard believes that by doing this it will decrease the inflation on secondary stats and make us want to favour our primary stats instead. Unfortunately for some classes and specs (Demo in particular comes to mind) the stats we are stacking directly affect literally every single ability and spell we cast/have.
With this change it will only make Haste even more important than it ever was before (there is exactly 0 spells or abilities, pets included, that don’t scale off Haste).
For simplicity sake I made a reference sheet for Warlocks (all specs/races) so that you can easily see the swing of your stats going into 7.1.5:
Reference Sheet with my current stats (non editable): https://goo.gl/4h5PEF
Reference Sheet that you can play with (editable): https://goo.gl/hUqw3w
UPDATE
Seems I overlooked that they buffed the amount of secondary stats on rings and amulets which offsets the stat differentials, for example…
Live:
PTR:
This led me to just make a brand new sheet with all my gear laid out by stat to show the % difference between them which can be viewed here: https://goo.gl/k10FWH
Just Nots Thoughts 