I'm fine with DE no longer wanting to make anymore Umbras. Honestly I see Augment mods + Helminth being no different than having an Umbra in its place. Could be even more of a cosmetic "what if" skin thing if they actually wanted to.
HOWEVER, I would still like to see other variant Umbral mods in the future. Stretch, Streamline, and Primary/Secondary variants are some of the possibilities that come to mind.