I’d like to see active perk upgrades added to the Current Upgrades dialog. That dialog already provides a one-stop shop for seeing the activity of your workers, of which most people only have a handful. In contrast, there are far more things to keep track of for perks and there’s no convenient way to do it. As it is, trying to manage perk upgrades is very painful as you need to individually select each spell, unit, tower, obstacle and inventory item to get its status.
If this is too much, can we at least get a notification when a perk upgrade is complete? Perhaps like the big green up-arrow when a building is complete? That way we can easily queue up the next perk upgrade right then, assuming there are sufficient pearls.