Your suggestions are quite loose though and need to be specified. .
We could set up the system like layers in ps. Off to the side of the screen may be a few check boxes. As you click the check boxes it starts to show different aspects of the map by simply layering one view ontop of another. So basic view is just the stars' name. You then click the "fleet" check box and you can see your ships. You then click "enemy fleet" check box and you can now see all the visible enemy ships. You can then click "empire" and see the rings around the stars denoting who owns them. You could then select ... ect.
What exactly should be shown?
Off in the lower righthand corner could be a white, semi-transulent eye. You click it and a small pop up window would appear. In the pop up window would be the name of the different layers with a check box next to them. As the player checks what they want to see it automatically adds that layer to their view of the map.
So what may the player check? Don't quite know, but at least nothing; leaving a starmap with only star names. Fleet, showing fleets (maybe divided into individual players fleets). Empire, showing the rings around the planets of ownership. As we develop more I am sure more windows would be helpful. Such as planets not currently producing anything, economical indicators, etc.
How do we get most out of it?
Make it start off with the fleet button selected and the empire button selected so it looks just like the game does now. Since it is small and off to the side it doesn't really get in the way and if a player doesn't know how to use it they play just as if they would without this feature. However, players who like to toggle between views to see possible patterns or weaknesses may find it quite useful and would use it however they find it useful. For example, I am bad at multitasking so a view letting me see idle planets may be useful to me, but others may find this useless. Hence the player gets out of it what they need out of it. Don't need it, don't use it. Need it, use it.
How is it shown exactly?
Talked abou this already, but to add to it; after you open up the view check list you might seperate it like folders. Fleet and then listed below it every player with a check box. That way if you only want to see player 2's fleet you could check player 2 under fleet instead of fleet which would check them all.
You'll quickly notice it's not that simple.
Yeah, but it may be neat and let us not worry about cluttering the board but rather let the player worry about that. Just a thought, nothing more really.