-Spd +Def Ares Assistance?

With how much hp he has naturally I stay use Quick Riposte. It would be best probably to have him in either a mostly cavalry team to get those buffs or buffs from other units like dancers. I think either giving him Fury 3 or Darting blow or if you have any extra's either atk spd 2 or any speed increasing if you are so dependent on raising his speed but I think just focus on his good defense and his already amazing attack and don't worry to much about his speed. I hope that helped.