The big problem I feel is that buffs generally have too short a duration. When you factor in an AP cost to use them, some of them come up pretty short, because after casting the buff on yourself, you may not be able to do anything else useful for the rest of the turn, wasting one of the turns.
Food and Potions having the same short duration as spells also is a problem. Differentiating them by having items give a longer buff time might be a good step.
