Any suggestion on manage 1700 users files gallerys and growing...?

Hi,

i've at this date 1700 users that have their own file gallery, now this as become a problem because the loading time of the tree view results in a "we can't serve your request" message. I need some suggestions on the best method to group the users like alphabetical order and by profile, or something else.

Any idea wouldbe useful, thanks!