It's okay. The old maps are gone so you don't have to worry about them any more.
Ha ha ha.
But no, they're still in the list there. I frequently switch maps depending on who is playing. I just thought it'd be nice to get a large group together on an even level for a bit to build and explore together.
Besides, if you were to place a piggy bank on our new map and load your previous character, you could grab his money out of it anyway. Pretty cool.
EDIT: About the NEW CHARACTERS ONLY thing, we're just now getting into a small amount of demonite gear.
Just letting you know what level we're at. If you wanna start a new map with new characters, you'll have to wait for another round. Please let me know if you're interested at all though.
Despite how many people apparently have the game, there is a surprising lack of interest being communicated regarding these multiplayer sessions.