chris broderick the "new" guy in megadeth is a beast. i dunno if he counts as "new" though.
tobin abasi (animals as leaders) is pretty crazy too (again i dunno how "new" he is)
and since orianthi is already in the conversation, let me bring up 2 chick-tarists who aren't
jessica garlund (give this clip time and she'll eventually get aggressive)
chelsea constable (older clip but she still shreds)