suggestions for deviantArt message center and for dA in general (color coded by arrows):
message center suggestion: tab display more than messages and notes according to types one may want to check. (if new is selected only new messages will be shown in whichever tab you are on - see blue bullet for extra info on this).
general suggestion: sidebars have separate scrollers so that the part of them you are on is always visible no matter how far down you scroll in the window. it scrolls if it's too long
general suggestion: floating menus. the top menu and the bottom menu stay in place and don't scroll with the rest of the window so that they are always visible and accessible.
general suggestion: new messages counter. whenever a message is recieved there is a unique sound according to the type of message (notes\feedback\notices\deviations\journals\polls\mentions) and the numbers of new messages are displayed in parenthesis. this is updated upon arrival of message wherever you may be within or out of dA (as long as a dA window is open of course). if "view new messages" is selected then only unread messages are displayed. if "view all messages" is selected then all messages are shown of every category. if one of the other categories is selected then the status of "new" or "all" messages remains as was selected last but only the messages in that category are displayed.
message center suggestion: a more comfortable distribution of the messages in the messages menu