Hi @ptimich,
You can add arbitrary elements to the palette. At the moment we offer UI Schema elements and the JSON Schema elements but you could also add elements representing a string, boolean etc. Of course you could also not be sooo generic and just offer (or additionally offer) often used properties like mail, name etc.
Once the user drag/drops them in you can then modify both the schema and the uischema accordingly instead of only the uischema. In the same vain, editing a label within the main panel or the properties panel could also be used to not only set a label in the uischema but maybe also adjusting the property name in the schema.
I’m not super deep into the current code base but I’m not sure whether this can be accomplished just by consuming the editor. It could very well be that some more API needs to be more exposed to being able to implement all use cases without modifying the editor source. However when using the editor just as a base and forking it this should be relatively easy to implement.
You might want to look at this PR where we experimented with making the editor more generic with string, boolean etc. attributes in the palette. You could to the same way, just offer your more specialized controls instead.