Would be good if you could include your hero in calculations when he is on a mission. Its annoying that you have to wait for the hero to come home before you can use him in calculations.
Also, some kind of 'whatif' mode - allowing you to select scrolls from the hero doll/vault to use in the calculation, without having to actually cast them (as you have to now).
Yes I know this can all be done with external calculators, but I am sure the devs would rather we paid for the ingame one

Which I must admit is rather more convenient being right there and not having to type everything in and set it up.