I don’t save settings for a couple of reasons. 1. it would take ages to maintain and keep up to date in the code and reject old settings that don’t exist anymore. 2. a setting could be causing a crash or bug and reimporting all the settings will result in the same problem.
Importing places and graphs do work. You deleted the graph from the place not the app. If you export the place, then change the place, e.g., delete a graph, then reimport the place, it’ll look the same again. If you export a graph, edit the graphs, then you import them back in, then your graphs will look like the exported ones.
This is a convenience feature so you don’t have to setup all your place and graphs again on the rare occasion you reinstall. Or to share with other.