might a pre-selection by first character of pre-name or last-name (oops, right words?) might help to get smaller value lists, and then a second smaller selection that is already reduced. to data records with the same first character? Try the example ABC-Zugriffsleiste.
Another way to make calculation of value lists shorter in time (but not shorter in length), is to increase client memory (Edit, Settings, Memory) and / or server memory.
If you think my example file is helpful, make a donation to a wellfare / charity organisation of your choice and show it in my online-database.
greetings from germany
Here's a technique I use. I allows you to search for a person by name, yet use their ID number to link records. Since it lists client names, you can enable auto-complete if you wish to make long lists a bit easier to use. If you find that auto-complete has too much of a performance penalty, the method can be used without enabling auto-complete, nor do you have to have a drop down at all if you so choose.
You can use a new window to allow your users to choose from a list view of records.