When I copy a table using the object browser, the new table name for me is usually the old table name plus the suffix "_BAK".
I want to be able to provided a default suffix for copied table names. If that field is set by the user, SQL developer should already fill the "new table name" field in the popup dialog wild <OLD_NAME> + <SUFFIX_FROM_PREFERENCES>.
Also, after I clicked OK on the "copy successful" messagebox, the selected item in the object browser should be the table I copied from.
The best place to submit feature requests for SQL Developer is on the Exchange: https://apex.oracle.com/pls/apex/f?p=43135:1
Click on the Feature Requests tab near the top then click on the Submit Feature Request button and fill out the form.