With the game being released as a downloadable game, will you be releasing covers on the site for people to print out?
Alot of people I know who download online games that they pay for like to burn the installition file to a CD so they always have a backup just incase anything happens to the one installed on their PC. So perhaps a CD cover uploaded on the site would be a good idea.
P.S. Can't wait for the game! I've played Adventure games for over half my life... most of them games your team has worked on.