Almost as soon as I set up my Squeezebox, I wanted a bigger screen.
My eyesight isn't great, and when I'm sitting on the couch I can't
read anything except the full-height text.  Thus I only get about 15
characters on the display, and no progress bar.  The two displays on
the Transporter still aren't enough to satisfy me, but if used wisely,
they could be a big step up.  As it stands, the Transporter is too
expensive for me, but if you implement some of these ideas, I'd be
sucked into a purchase (assuming I don't go broke in the mean time).

Here are some suggestions on how to use the displays:

*) Allow display any of the available "formats" on either display
independently.  Pick the font size for displays independently.  Thus
you could have the track name in big letters on the left, and the
artist and progress/time on two lines on the right.  Like so:

    Left display                    Right display
----------------------   |   ----------------------
   TRACK NAME                Artist's name
                             3:54  [|||||||_______]
----------------------   |   ----------------------

*) When looking for music, you could display the type of index on the
left, and the current selection on the right:

    Left display                    Right display
----------------------   |   ----------------------
   Browse Genres:             43 of 176
   Heavy Metal                Grond the Destroyer
----------------------   |   ----------------------

Or, for us sight-impaired folks:

    Left display                    Right display
----------------------   |   ----------------------
 Genres: Heavy Metal           Grond the Destroyer
----------------------   |   ----------------------

*) Take advantage of the difference between the front-panel knob and
the remote.  When the knob spins, the user is obviously close to the
box, and thus you can use a smaller font.  Heck, you might be able to
pack three lines on the right display, so the user can see the next
and previous entries:

    Left display                    Right display
----------------------   |   ----------------------
 Genres: Heavy Metal          Grotus
 43 of 176                   >Grond the Destroyer<
                              Hammerhead
----------------------   |   ----------------------

When the user hits "play", switch back to whatever now-playing format
they've configured.

*) Instead of cycling font size with the remote, cycle through
different display formats.

*) Allow users to build arbitrary display formats.  The Rockbox folks
(open source OS for Archos/iRiver/iPod players) have a really neat
system for this; users make and trade formats.  Check out the docs:

http://download.rockbox.org/manual/rockbox-player/rockbox-buildch9.html#x12-1340009.2