Corran. Maladi has some TK and sorcery that should make her dangerous, but her dueling isn't going to match up against Corran's, and she also likes to use lightning.
If Maladi avoids lightning, she has some chance with her sorcery but more likely Corran outduels her, and it's not like his illusions are bad either. If she uses lightning, things favor him more and things end quicker and more decisively.