Honestly, no Sense in going Elite since it's a Straight +Defense.
If it were +%Def that would be a different story.
If you go with a Normal Breast Plate (65-68Def. Light Armor/Lowest Str with 3 sockets) and you roll the lowest possible defense on Enigma (750), You'll still have a Total Def on your armor of 815.
If you go with an Elite Sacred Armor (487-600 Armor with Most Defense) and you roll the Highest possible defense on Enigma (775) you'll have a total def of 1375.
Of course, it's the Low Str Requirement that matters. A Dusk Shroud with only 27 more Str required than the breastplate has roughly 300-400 More def.... In that situation it may be worth it. I just wouldn't recommend a High def armor with an Str Requirement of over 105... The +Str from Enigma will at least have something to do if you wish to Wear SS or a big weapon.
If you have a Sacred Armor, it's basically just for More ed% and I usually concentrate on life more than a Titan Build.
Generally speaking, don't go too high on Str. Most Important. Take Advantage of the Str provided by Enigma for your other gear.
2nd most important point. Light Armor if you ever plan to Duel.
3rd.
Style
4th. Defense because that +Def from the Runeword just overshadows the base def.