Either by renaming the current "Tiler" to "DatasetTiler" (or similar), and create a new "GeometryTiler" transformer, that works on individual tiles/geometries.
Or by adding a dropdown or checkbox to "Tiler" that enables tiling of individual tiles/geometries instead of the whole dataset.
In a feature-by-feature workflow it makes sense to have this kind of feature based functionality.
Cheers
Lars I.