A thought I just had ... would there be any constitutional issues for Congress to direct the US Virgin Islands, Guam, and the Northern Mariana Islands to hold presidential elections, and to allocate those 3 extra electoral votes to the winners of each of those 3 territories?
It's still not full equality for them, but it allows those Americans to have some say in the presidential election process, better than nothing.
No, since the 23rd Amendment permits Congress to direct the appointment of the 3 district electors however they see fit.
The amendment specifically says "District constituting the seat of the Government," which means this trick wouldn't work