I tried to play something with my 3 finger grip on the D and G, and then in B and E. I like doing this sort “cross picking roll light” exercise, where I do GDD GDD (DUD UDU). Picking single notes feels extremely different than this “cross picking” thing, and also bluegrass lines. It feels like playing bluegrass lines and cross picking require more movement in my hand. But I can do it fast (132 bpm). A 2nd thing I tried was trying to have my pick be more “vertical”. I think I could still do better in that sense.