If we are lobbying for different shapes then I vote for a Cube.
You know it must be the most efficient shape since the Borg use it.
And just think you could have 6 different alt-history empires going on at once.
booooooooooooo! my preferred map is a pair of 20-sided dice! i can play 20 PDS games at once while in the middle of a Dungeons and Dragons game!
...wait... it's the perfect crime! a runemaster DLC for D&D! ok paradox interactive, your move!