Unfortunately, I was trying to keep stat point distribution fairly even, so I'm convinced I need to give it another go with a new character.

So if I'm not going to focus in an area at all, I shouldn't bother with the related stat? Even if, say, I need some damage resistance in that area? (IE, ranged resistance via DEX).

I've already concluded there's not much reason to put more than one point in Mana Leech, since it seems plenty effective with one point. I did put multiple points into Potion Efficiency, though the difference has seemed so minor I think that was also a waste.