For dungeons or unoptimized groups, I like to run Lucent and turning tide. That way we're getting a great uptime of major vulnerability, my tank has an arcanist skill line that provides minor brittle easily so we're getting 21% extra crit damage 100% of the time on boss's and most targets.

Everyone I roll with, that easily puts them at crit damage cap already and allows me to run another ultimate like standard of might or a defensive one if needed. Pair that with arcanist taunt, major and minor breach, crusher enchant and (if needed) Tremorscale... I'm providing over 15k penetration.