When adding a new Local Device Provider the wizard announces additional settings to be available after the provider has been added. That’s bad because adding the provider will immediately trigger a sync using expensive default options like looking for external images or lyrics.
To add a Local Device Provider I’d have to add a small sub-folder first, wait for the sync to complete, then change all settings and add the “real” folder I’d like to sync.
Only one sync required to import the whole library using the correct settings.
Other application solutions:
Not really aware of other solutions. But I guess you always can change all settings before starting a sync.
Additional description and context:
I had other problems with the local device provider requiring it to remove the provider and re-add it afterwards. So for me it was not like a “but you only add the provider once” thing.