Just got the Locust SMG. Pretty low impact damage, but it's accurate as f**k and beautiful at supression. I'm not sure what I'll use it for most, because I wanna have the Hornet in either my Infiltrator or Asari Adept class... thinking of keeping my Locust for my Adept (weakening and then Throw), but they're both awesome guns if used correctly.
As for the coming Asari Justicar class, we've already seen that it has the Throw ability, and the Biotic shield as an exclusive ability, but I'm hoping the other secondary is Slam-- really wanna see that make an appearance in MP.