Raiments still is lagging behind the other builds, and one big issue is that the set bonuses offer no damage mitigation.
One idea, that also plays well with the new Combination Strike (which encourages you to run 3-4 spirit generators), would be:
4-piece: Additionally, reduce your damage taken by an amount equal to your dodge chance.
This would change some choices up (Dashing Strike would always opt for Blinding Speed instead of Radiance; Guardian’s Path would be MUCH better; Mantra of Agility would be must-have), and allow the dropping of Unity. The build could even opt into Focus + Resraint, maybe with Hellfire Amulet for a 5th passive?
Obviously, some kind of just straight damage mit, a la Crystal Fist, would be less constraining on possible builds, but I thought this might also lend a unique-ish flavor to the Raiment build.
Like for many other classes, aren’t there other items like bracers (Spirit Guards? in this case) that add the damage mitigation. Demon Hunter often has to deal with Elusive Ring, Barbarian gets Band of Might, and many people are familiar with the multiple restrictions on virtually every Witch Doctor build… seems that’s the thing for classes. Sets are primarily offensive.
There are bracers for Raiments build. But almost every other 6 piece set in the game also provides some damage mitigation. Raiment is the only one I can think of that doesn’t (my knowledge is not encyclopedic). And with the fists also being taken up with a set, just to get damage to an acceptable level, the options for other class items (like Crystal Fist), evaporate.
There are only three (?) sets in the game that don’t provide some significant type of defensive (toughness) set bonus: raiment monk, raekor barb, and tragoul necro. However, the tragoul necro gives you a huge life pool buff, which is a form of toughness. The devs never explained why raiment and raekor are noticeable exceptions to the set bonus trend. You can’t say “well there are defensive support items you can use” when sets that DO have defensive bonuses can also use those support items to FURTHER boost their toughness.
As for the original question, stop thinking complex, and go for the simple route in design. Just move the “crystal fist” legendary bonus to the raiment set, which gives 50% DR for 6 seconds after using dashing strike, which you’re using frequently anyways.