The builds you see on the sight tend to 100% require at least the set pieces, and often times additional pieces to be worth anything. Generally, you gear according to what legendaries you have.
Quick rule of thumb - 1-2 supporting legendaries for 1 skill (For Barb, things like Bracers of the First Man and Gavel of Judgement, theres numerous other examples)=T2-3, 2 set piece+1-2 supporting legendaries (Monk, 2 piece Innas+Crudest Boots)=T3-T4. Once you get a 4 piece+supporting legendaries, you can move up to T6 (For a Barb, I've found that getting 4 piece IK+Bracers of the First Man allowed me to do T6 easily).
For your monk, theres only 3 sets to go for - Inna's Mantra requires Monkey King's garb to really shine, so I would not recommend going for it. Ulliana's is strong just with the basic set, it has numerous supporting legendaries so you can get up to TX with all of them, its only problem is that it lacks
Currently, with the double bounty bonus, I would STRONGLY suggest running Bounties, and nothing BUT bounties for the weekend, as you get double blood shards (making Bounties just as good as rifts currently for Blood Shard collection), double mats (VERY useful, especially when you get into the reforging portion of gearing), all the legendaries (Also useful), ect, ect.
Use Kunai's Kube to acquire supporting legendaries, especially with the Diablos/Fist Weapons/Spirit Stones.
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