Grimoire is generally useless. I would go by k/d from patrol and crucible. Generally decent people will be higher than a 1.0 k/d in crucible. Decent on patrol would merit 150+ and really good are usually 250+ across all characters. I use the patrol because it generally estimates how well you play without trying very hard and without forced deaths you generally experience in the raids or PoE. Usually people under 100 k/d in patrol are pretty awful all around.