deviant Sidebar
Everything has a sidebar these days, from applications to websites... and the reason is just because they're so damned functional. Choosing one for deviantART was only logical. I picture everything below the "Avatar, Name, and Stats" sections being closable/hidable, reducing them to simply the green bars with the titles.

My Quick Links
Not a stretch from the Navigation bar up top (in fact it's really no different at all, barring the look), but I think having them more centered allows them to be more useful, and when used in tandem with the Navigational icons above, you can then double the amount of actions you can make within deviantART. Or, for those of you who may not like the Navigation icons above, hide them all and simply use your Quick links in your sidebar!

My Control Panel
for all this stuff, you've got to have a place to house it. Enter the "Control Panel".

Profile Module Management
Think of it like iGoogle, My Yahoo, MySpace's internal modules, or your profile on Facebook. Arrange your entire Profile page (by module) how you like it, restricted only by columns. Your choice of two or three column layout. But then, imagine you can make public or private any module you like, as well as take advantage of a "minimize" feature in the event you'd like to have them all available to the public but are worried about it looking too cluttered with them all "open".

Deviant Power Mode
All of these are for the most part self explanatory, and not unlike the items above, would all be easily turned off and on with the click of a box. I do want to touch on a few of them, however.
Power Tutorial: basically, dA tutorials that are integrated to encompass an ultimate link and module augmentation multi-tool. The goal would be to provide deviants with excellent previews, useful extra information, and relevant next actions for almost any given link, section, or module on any given page.
Power FAQ mode: Just like the tutorials above, and relevant place that a deviantART FAQ might apply would create a mini pop-up window displaying the appropriate FAQ links----and perhaps even the Question prefacing the answer.
Condensed Journal: cut the available front-page text to half of what it is and offer a "Click here to read more" option at that stopping point. Many people loathe scrolling down a long page.

Collections Module
I felt this was very important to add, because as it is our recently collected Collections are shown NOWHERE beyond going into our favorites gallery. It would better our experience, I feel, to have the option to display these. Let's face it, Collections rock!

More, More, More
I've made more room for displaying more things in this design, such as Recent Deviations, Submitted News, etc. And while it seems as though I've cut down in other areas, such as the Wishlist, i have in fact presented them with the ability to Browse directly from the profile page, from first to last, one at a time. This is the same idea with our Featured Deviation.