I was pondering something the other day...

What if DRK were able to use a Sublimation-like effect that drains HP and increases attack? It could be stored up to say...1/4 of your max HP, and when used could bump your attack by a variable of the amount of HP stored? The attack bonus could either be used for one attack round, OR stay in effect for a set amount of time, whichever most of the player base would prefer.

Another idea would be an ability or job trait that utilizes debuffs on the player. Say it has a chance to transfer the debuff on you to the enemy via an "enspell" effect. For example.

-Player is inflicted with blind.-
-Next attack has a chance of transferring blind to the currently targeted enemy.-

Alternatively, the inflicted debuffs could be used to increase the strength of the DRK. Say having 1 debuff increases your attack by X%, but having 2 debuffs increases it even more.

Both of these abilities pay homage to the lore of the Dark Knight, such as using one's own suffering to inflict damage to enemies. I haven't played DRK since 76+ has been obtainable, mainly due to the utility of the job becoming irrelevant to other jobs' strengths.