If there is grouping, there is possibility to have many launchers in desktop than normal. So, May be the bottom panel can be completely removed.
Because, In Ubuntu we have two panels by default, which comes in the way of users, less screen space to work. So may be there can be a smart-group for currently opened programs, right on the desktop. Hence totally eliminating the need for the bottom panel. There is only workspace switcher and show desktop in it. Which can be moved to top.
Also,
1) There can be custom groups, Say I'm a web designer I want to have all my web design related apps in that groups, and if I'm a part time dj, I would have a seperate group.
2) There can be smart groups. Say If I'm a photographer I save lot of images, Then there can be smart groups, which means if certain file types such as jpeg, png were stored. Its instantly grouped under a custom smart group pictures.
Just checked out fence, Its is a very basic program, which just makes a background for different set of icons. But, the idea I proposed, is grouping icons and which makes one group visible at a time. So, If desktop can have 40 icons, by this system it can have 200 icons if there is 5 groups.
There could also be a scroll bar, so that there can be any number of icons under a group, But, I'm not sure, how many will like the scroll bar idea, But definitely It'll be a great useful thing for desktop junkie like me.
My solution (#3) could be expanded to include grouping as a submenu of the different desktops. Just realize that solutions aren't mutually exclusive. If anyone has advice on how to improve my solution, I would consider revising it. Thanks.