Data Tools Filter Component - custom filter fields dropdown

Greetings,

Is there a way to use a custom dropdown component for the filter fields (similar to the FieldSetting filter prop) when adding an expression?

In my case there will be hundreds of possible filter fields and ideally I'd like to use either a grouped DropDownList or a DropDownTree component to display the filter fields.

I haven't seen that this is possible from the API or demos, nor have I seen many forum threads for the Data Tools Filter in general.

If this isn't supported, is this a feature that may be added in the future?

Thanks,

Alexa