Brave Sword and/or Silver swords are excellent. You either have a killer sword or super hard hitting, both are great because they have 90+ accuracy which is important when you're basically dealing with 20 avoid on a bad day.
Rhomphonia is good and cheap to upgrade, that +Speed modifier basically makes Matilda or Clair a one-shot machine and you have two mages that shred horses by the time you can upgrade it.
Killer bow is obvious.
Silver Lances are powerful for the same reason silver swords are. Accurate, powerful and decent skills when needed.