Not quite clear as what davebt was trying to convey, but if one is uninstalling because they do not like the application, why would one want to keep anything?
Also, I have installed, and subsequently uninstalled, all the 2017 versions, from the first BETA through the latest release.
I have never uninstalled X, except the one time I tried to use X to remove the leftovers of 2017, and it uninstalled itself (X).
Here is my suggestion: When running the uninstall routine, a prompt asking if the user wants to keep any data should popup with YES/NO as the two options.
Selecting NO completely removes everything.
Selecting YES results in another prompt asking the user what they would prefer to keep, e.g. License, Backups, etc.