Im playing rogue assa in cata classic and after read some guide I don't understand some things about stats. 
I know as a rogue assa I have to priories hit rating until the spell hit cap of 17% (1332 if I remember) but i dont understand how to manage other stats like mastery and haste/crit or expertise. 
Did I have to put full mastery ? and reforge all the crit chance, expertise and reforge haste at least ? Or did I have to balance mastery and haste ?
Can someone help me to understand in wich ordre and priority I have to manage stats as Assa Rogue in wow cata classic ?

As the title already said I'm needing help understanding how to make the build like the guide says, i somehow need to get the full set bonus of bones of Rathma but i also need the full Captain Crimson's trimmings bonus for cd reduction i can get that with ring of royale grandeur but i also need to use fate's vow helm but if i use it i cant get the full Bones of Rathma set bonus or Captain Crimson's trimmings bonus. 
If anyone know how i can get that build to work please say how, I'm open to any suggestions.
Link to the guide I'm  talking about: https://www.icy-veins.com/d3/necromancer-rathma-army-of-the-dead-build
(this is my first post on icy-veins and i don't fully understand if I'm doing this right) 

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This thread is for comments about our Outlaw Rogue Leveling Guide.

I am going the corpselance support build for Necromancer and the build has me taking Corpselance with Brittle and the pestilence set on top of that, if I were to take off the ability Corpselance and change it to another ability say for example Bone Spikes with Frost spikes, would the damage decrease an amount that it would not be worth it?