In the main lounge, basically when you join online, when a game is created, there should be some info next to it, such as size, and how many players are in/availible
so, such as on triangle it would be
or something along those lines. A breif thing above the white box telling what each section is would be cool too, making it more of a table like thing.triangle - 128x128 - 2/3
Then, once you join the game, inside it will have a preview of the map, such as in the lounge one, along with the size, if fruit vision will be enabled or disabled, etc.
I found that very helpful in starcraft.
Cheers,
Kyle