MS Visual Studio has a great feature: it automatically suggests the units to add in using
clause when you typing the code with refrences to absent standard classes.
The JCL includes the "Uses Wizard." It watches for compilation errors mentioning "Undeclared identifier," and when it sees one, it automatically adds the unit where that identifier is declared.
The package JclUsesExpert.dpk is only available for certain Delphi versions. I don't know if that's because the plug-in doesn't work in later versions, or if someone merely neglected to copy the project into later versions' folders.