Currently an item is either equippable or consumable as far as I can tell.

Being able to have something like a 'Wand of Fireballs' that can be equipped, but when its charges are expended it disappears like a consumeable would be nice.  Can't see a way to do this currently.

Also single use items that hold spells, like scrolls, that can either be used Strategic or Tactical depending on the spell. Haven't seen a working example of something that can do this exept for SummonUnit.  Maybe I just don't know the proper coding.

Being able to create a 'Staff of the Magi' would be awesome.