Hey Turk, appreciate your input but this isn't really meant to significantly increase DE's power level. It's intended as more of a very minor buff to make the gameplay more fluid for DE. The mark is a key part of the initiation to combat for the DE, and isn't an incredibly high impact skill upon activation compared to steal which is a strong gap closer, and compared to instant activation skills of other classes. In its current state, having to remark new enemies as they die really slows down combat in PvE and makes combat in PvP fairly sluggish. I am aware of some potential interactions with mercy but I think that's a fairly fringe build and a change to .25s wouldn't break anything.
