Deadeye's Mark is rifle only?
Mark works on all weapons. If you’re good with core thief. You really don’t need to worry about people getting into melee range of you, because you’re just as nasty up close and personal as you are far away.
Mark does not affect condi damage though, so you are pretty limited to pistol #3 and power builds
Yeah, maybe a hybrid build could get more out of it?
The base damage increase is nice in concert with might stacking builds because it will hit decently hard regardless.