Is this a matter of propagation? I’ve seen this too when I delete a data field called “applications” (yes, confirming to delete dependent host assignments), and radding them, they never show up:
You images shows only that you try to make cubes for services and not for hosts.
If you want to do it for services also, the variables need to be inside the service object, it will not work for variables from the host.
And it will not work for arrays , but i remember that there should be an open issue for this.