I repeat my points about biotics from another thread. Hopefully some of these issues will be dealt with in the next patch. Fix these issues and you fix her. Stasis is still a wonderful power by the way. She has warp and throw to deal with armored enemies and stasis to remove shielded enemies from the picture.
Weapon spam >>>>>>>> Tech spam >>>>>>>>> Biotic spam
Biotics suck compared to weapon spam classes because:
1) Biotic powers do poor damage per second
2) Biotics do poor damage without biotic explosions
3) Biotic explosions can be very difficult to pull off in public games because:
a) Everyone guns for whatever target you prime. Seriously.

Tech powers and tech ammo (which everybody uses) overwrite your
biotic prime. One overload spammer/tech ammo user can shut down your
BEs completely if he wants to.
4) No equipmnt at all increases your BE damage, which is the main source of damage for biotics.
5) The increase in biotic power damage from consumables and gear is negligible.
6) Biotics tend to have poor hit points/shields and run and gun has been forced on everyone on every map.
7) Anti power enemies
8) Anti power faction (collector)
9) Insane dodge rate of projectile powers
10) Nerf of biotic expolosions that happened a while back.
I probably left some stuff out, but you get the idea. Bioware made a
conscious decision (it appears) to make weapons and grenades dominate
the game.
Biotics in public games are a pretty rare breed as a
result. And those few you see are mostly packing overpowered weapons
like the harrier and use that to kill enemies instead of focusing on
their powers because their powes are so ineffective compared to weapon
spam.