Right now, the List Box interface tool allows end users to select multiple options of fields for selections, filtering, and formatting/formulating.
However, it doesn't do quite as good when a use case has over 1,000+ columns/fields. This is made even more complicated with each column/field having somewhat similar naming conventions thereby causing confusion.
Having a search function, as made available in standard Select Tools, Join tools, and other tools that has filtering capacity, will be most helpful for developers to give maximum flexibility to end users.