Again this is not a necessity, but just a little step towards a cleaner workspace.
For transformers that can expose attributes that you didn't create yourself (e.g. JSONFlattener, XMLFragmenter etc. but not the PythonCaller), I would love to have an option to be able to directly rename the exposed attribute. Also, setting a default value might come in handy, as well as the possibility to populate a list of attributes (import from a file).
So something like this:
