Awen can create pretty much anything from Spirit Flame at will. And depending on what she requires, it can be as solid as diamond or as liquid as soy sauce (which we all know comes out of the bottle faster than the speed of sound), so she could probably block most attacks pretty easily.
And even though she's from a culture that doesn't typically use melee weapons, she's still a pretty respectable swordfighter, even if Xander likely beats her on that front.
So I think, in Awenasa's case, her good defense is going to be her victorious offense. Simply because she would probably block most of Xander's attacks until she sees a good opening to attack.