Mastery is ur bis stat. Crit is nearly as good. Haste is the 3rd for single target and multi is the 3rd for AoE. Vers is just the worst stat. keep in mind if the item is upgradet by 6 or 7 ilvl dont mind the other stats. the int boost will be enough.
For trinkets it depends on the fights and stuff like that. ur primary trinkets are Goren Soul(Int, Procs crit. Drops from Oregorger) and Darmac(Int, Procs haste. Drops from Beastlord Darmac) if u can, then get Micro crucible(Int, Procs stacking multistrike. Drops from Blackhand) which is better for AoE fights like Beastlord and Beastlord then Darmacs.
So in short
Single target:
Mastery
Crit
Haste
Multistrike
Vers
Use Goren Soul and Darmac
For AoE:
Mastery
Crit
Multistrike
Haste
Vers
Use Goren Soul and Micro Crucible.
PS: I dont know if Micro Crucible is spelled right :P
I'd imagine you'd want the Alchemist Stone, and either Copeland's Clarity or Shards of Nothing.
Alchemist Stone because of the very short ICD (and you don't want two on-use trinkets). Copeland's or Shards are good simply because they're on-use and give you more control over your burst, where as proc trinkets can screw you over somewhat in CMs.
not sure why we are discussing copelands, its a good trinket, but if you can't afford it why bother discussing it.
from BRF the darmac + oregorger trinket is best, with the blackhand trinket being discussable for cleave/aoe, swapping out the darmac trinket, due to haste not affecting starfall.