A feature that may have its uses...
When adding a brush to a custom palette sometimes it may be desirable to put the new brush at the top or middle of the existing contents.
Currently that means individually selecting every brush and moving it to make room.
I notice the "auto move" function already exists for organising paper libraries. The user can take a favourite paper and drag it to the top of the palette, causing all other papers to move along and make room.
If this function was available in custom palettes it would be EXCELSIOR!