The map should be the main user interface, most functionality should be accessible from the map. Screens such as research should be overlayed over the map if they are opened.
The map should be a javascript enabled interactive map with context menus and nice graphics for planets and fleets/ships. Various information can be enabled and disabled (system names, system owners, fleet information etc). The map should scroll smoothly and it should work intuitively.
The layout should be similar to the gmail Planets theme, dark grey blue with beautifull background images. The background image might depend on what race a user is playing or game functions, e.g. if the user has selected a system the background image could resemble the type of the system (arid system: arid planet in the background).