Crit and status chance are modified by combo counter ([Blood Rush] & [Weeping Wounds], respectively). Use a [Deconstructor] on your sentinel to get access to the other Gladiator mods and increase crit chance further (extra 10% per Gladiator mod in the set).

Berserker can be substituted for [Quickening] for a lower attack speed but greater combo count chance. Likewise [Vicious Frost] can be substituted for [North Wind] but it will take longer to build up status effects and damage from [Condition Overload].

If you instead want pure corrosive damage, drop [Vicious Frost] and use [Quickening] instead; you'll wind up with better attack speed and the combo counter ramping up faster.