This would provide greater latitude for animating objects, especially by using customVariables or doors to enable/disable certain animations.
They could be nested for more complex logic, like
"and": { "variable": "customVariable1", "nand": {"variable": "customVariable2"} }
At least initially, these can be limited to boolean variables, but eventually, they can use clampMin and clampMax as is currently possible for non-booleans with visibility.