Greetings :)
Are we talking about card sorting (which doesn't filter cards out, only determines in which order they appear on the list) or are we talking about card filtering (which removes some cards from the card list, but doesn't effect list order) or both?
Currently it is possible to filter out cards that match only a specified card cost type (red, green, blue, ...) and order is fixed alphabetically (ascending order).
If I undeerstand correctly, your suggestion would be to add new 'cost range' filter which would apply to total card cost (bricks + gems + recruits), or rather partial costs (bricks, gems or recruits)?