is there a right or wrong answer? i like the soul cloak, amulet of rao and parasites power harness. i just find the way I play it makes everything go smoother. im almost never out of power, i regenerate it faster than i dump it, i debuff the hell out of everything and being able to fire off power giving force fields with frequency makes me a hit around the ole water cooler. i've tried other artifact combos and found them not to my liking. I hated the BoP troll artifact. I fed it to my soul cloak yesterday.
Rao/parasite/cloak is the standard troll setup If your going for more of a buff play style get the claw or just keep the cog you will run into players who still use precision. Or you can replace cog with soul cloak for supercharge regen
To be honest, all troll artifacts are viable, the devs definitely made the right decisions when designing these. with that being, said you can basically combine anything and give a viable power output