So I was looking at Parry, thinking how worthless it is currently, and wondered: what about Riposte?
Riposte was in Everquest (and possibly other MMOs, I dunno) along with Block and Parry. Different implementations, but same general idea. Riposte is the passive defensive ability that randomly mitigates an incoming attack and strikes back in same motion. Since SE has no problem incorporating Block and Parry, why not Riposte too?
This could be linked to the Parry stat. Or paladin's block. Or both.
Riposte could trigger on some % or all of Parry/Block.
The attack component could have varying potency: from an auto-attack on down to 20 or 50 potency like a DoT tick.
There is already precedent in Vengeance or Sword Oath for similar "strike back" or "additional strike" mechanics.
If linked to Paladin's block, Riposte could give them a bit of a DPS increase - more so than other classes. Also would thematically tie to the defensive focus of Paladin. Defense as offense basically.