The simplicity of fewer action points is nice, but I do fear it'll actually dilute tactical thinking. Maybe not, though 6 does sound like a more ideal number to me as well. Then abilities could cost between 2-6 AP, and you'd usually have a bit more leeway to use some AP for movement, instead of only having 1 AP to move in a turn. Would let you make a move, use ability, and then move again, where that's basically impossible with 3 AP.
It would be interesting to see "movement points" as a separate currency from AP, kind of like how it works in DnD, 5th edition, where you can always move and still perform an action in one turn. Speed would grant you additional movement points, and you could use your AP to move as well (but not your movement points to perform actions.)
This would take some fairly large rebalancing, but I think allowing for more mobility would be cool. It also might actually be easier to program NPCs if they don't have to evaluate whether movement or an action is more important, but can almost always do both instead. An NPC that runs back and forth like a headless chicken generating attacks of opportunity will still at least be able to cast a spell.
An unlikely change, but might be worth testing at least.
