Isn't that why there is a bunch of belts/gauntlets of XYZ Giant Strength in the game?
Give her a nice belt, the biggest, baddest armour, the shield that reflects missiles (can't remember it's name anymore), alternatively some +5 shield and either flail of ages or a mace of your choice. She makes a good frontline fighter and a good cleric (high wisdom).
Edit: I can't remember if there are things she can use that improves her innate magic resistance, I should keep an eye out for that next time I play