- strength == power boost that only affects the "naked" hero power
- equipment strength == power boost that only affects gear power
- survivability == power boost that affects both hero and gear power
(yep, it's confusing...)
About arena gear and breaking: it can break, but only for the duration of the fight and is back fine at the end of the fight.
Hmm, does set bonus disappear the moment a gear "breaks" in arena?
If not, then there are 3 options for arena gear: "0%" (for mythical +/-4 lvl for white/grey affinity, +/-5 for yellow affinity), at the top end of the set range (+/- 6 lvl) or as high as possible (caps at 4% break chance for mythical) .
as of 2016-09-11: Player level: 44, City: Eolythes, Blueprints: 517, Mastered: 419, Crafted: 78.61K
(except for tier 1 and some tier 2 artifacts mostly running my shop/gearing self sufficient)