I’ve been searching through the forums to +1 this and bring it back to the top. It’s a requested feature for the dLive and the SQ as well.
I usually don’t mix using DCAs but subgroups because of the additional processing that comes with it. I then end up mirroring my subgroup setup in DCAs and using the soft keys for the DCA mixes, just to use the spills.
Having group spills would speed up my setup workflow, be less error prone (because I often forget to mirror mid-show changes from my subgroups to the DCAs) and even potentially free up softkeys.