First, I'm going to say that undead are neat. I'm not discounting that there's a lot of great variety to the different undead streams. That said, a lot of the value proposition of Mummy Dust has shifted post scroll change. Previously, even if your best undead were still coming via the 1/day radial ability there was an argument that it was worth the epic feat because you gained a boost to the tier of your animations made via disposables which meant that in a pinch you could try and brute force problems via moneymancy. After the removal of MD applying to scrolls however it's essentially an epic feat equivalent to GSF: Conj. I could see the argument that in theory it's doing double duty as a GSF: Conj and Planar Conduit equivalent for undead but imo this is a bit optimistic given that the non-radial undead (those made via Greater Create Undead) are, in my opinion, not comparable in terms of performance to what someone casting Summon Monster IX can achieve with GSF Conjuration.
To this end, I propose baking the undead tier boost into GSF: Necromancy and reworking Mummy Dust to be either a bit more amped in terms of what it brings out vial the radial menu (to bring it more in line with Planar Conduit) or to be redesigned as some sort of minion oriented ability that has some sort of useful effect when used in tandem with active undead.