Skorn with LS 
because:
1) Allow us to use Rend with Ravage rune to increase range within 17 yards, more mobs get Rend(ed) = more LS
2) Free-up Bloodthirst passive for Brawler or any other useful passive skill as per personal preference
3) Can use TWH instead of IK Tribal Binding (LS) to gain +aspd / chd which is both very important stats for Skorn build to be effective (fury management / tornado tick / WOTB / CHD boost will determine whether 1 or 2 Rend needed to kill white trash mobs etc.)
4) Skorn's LS usually 4-6% which is almost / equal / more then IK Tribal Binding's LS + Bloodthirst combined
Conclusion too much pros to give up if you're seeking / using Skorn without LS IMO.
Regarding whether Ruby /
Emerald in Skorn, use
Ruby to increase Skorn's base dps if you have limited budget because high DPS Skorn with good stats are usually expensive... use
Emerald of course the obvious choice if you can afford / found a high base DPS Skorn.
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Yeah bro Haruan, I almost lost it with those endless green bats shit~! I apologize to have led you and Deckard into that trap

That is the skorn with highest dps and CHD I can find that time in AH. Others are some like dps reach to 1600 but CHD only got something like 140~150. I inserted ruby because it's base dps was indeed low. Now I'll be crafting amulet with CHD, AR, AS, CC, STR, VIT & Life% maybe (crazy price at AH). Wanna try if I can rach 200k+ dps unbuffed.