Search Download Size

Hello!
I am starting to think about the performance side of my app. My User Type needs to be quickly searchable, and it contains Data fields which are lists of other Data Types. These lists won’t be long 1-30 elements. When Users are searched for and displayed in repeating groups, does only the unique ID of the linked data types need to be downloaded or the entire contents of the linked data types?
I am considering making my User data type lighter by adding satellite data types to it and dumping all the lists there, but I don’t know if its worth it for small lists (of data heavy data types)

This might help