The last few days I haven't seen one single Underdasea map. And that is the main Eggwars map I play. But on the boards there are always like 4 or 5 aztec maps where only 2 have some people in in and the other ones are empty. Some goes for teaparty. I don't know if it's fully random, but those two maps are always on the board. Multiple times. Isn't it a good idea if there would just be one sign for each map and once the lobby is filled the sign will link to another lobby with that same map. So you will always have the option to join the map you want and it's handier to play with friends.