Yeah this is pretty good. While I would have ideally liked it to be an out-of-game thing, since going away is not always planned days in advance for me (particularly if work-related), I could probably live with this. Any outlying bases would die, but if properly prepared, at least my main base could survive.
Seems a reasonable compromise, since protecting a base then entails making sure it’s worth farming up a god token for, which should limit or remove spamming and griefing - and if it was radius-based it would make those damn decay umbilici worthless.
It would limit one’s base design if it had to fit within a god bubble though, so I’m not totally enamored with the concept, but I guess beggars can’t be choosers. Combine this suggestion with a slight increase in the general decay timer (8 days instead of 6, say) and we’d be golden IMO.