Have each list be collapsible - maybe have a setting where certain lists could start collapsed when you load your items page?
I like that you can collapse "Items You Own," but I have some NP lists mixed in with my NC lists that I don't always want to view when I load my Items page. It would help to be able to individually set those lists to say collapsed when I load the Items page! :)
DTI is a fantastic tool - just came back from hiatus and am absolutely WOWED by how well the site caters to users' needs!