...how much more she will enjoy an all-mtn carving board like a Burton Coil or Wire, a Prior 4x4, Donek Axis, or Coiler All-Mtn. I'd stay away from an Alp or anything with a square tail at first - not forgiving enough.
Has she tried Orthotics? That could be the cure-all. It sounds like she has sensitive feet, in which case orthotics and moldable liners will be wise investments. TD2s wouldn't be wasted on her either, because they allow you to experiment with many different combinations of cant and lift.
Actually the board can be your last purchase. Try hardboots on her current board. If she hates it, then you know you don't need to buy another board!