Wire hardening at a low temperature of orthodontic wire would enhance all EXCEPT:
Strain hardening—The increase in strength and hardness and decrease in ductility of a metal that is caused by plastic deformation below its recrystallization temperature; also called work hardening.
A wire can be fractured by bending it back and forth repeatedly. During each bend, the wire is cold worked, which requires greater stress to achieve subsequent bending deformation. However, this results in decreased ductility. 
When most metal alloys have been stressed beyond their proportional limits, their hardness and strength increase at the area of deformation, but their ductility decreases.
Ref: Phillip’s 12th edition page 58, 396, 402
Stiffness
Resiliency
Brittleness
Ductility