There should also be customizing your character (Adding accessories like hats, shirts, etc.), and bounce blocks, where when you step on it it launches you up like a spring. That's all I can think of right now, I'll add more as they come to mind. Sorry for the humongous comment that took two comment spaces.
I think (Ugh... This is gonna be a long comment) that there should NOT be a chatting systems. It would be nice, yes. But all the trolls and spammers would be FLOODING it. I also think there should be teleporting bricks, moving bricks, sloped bricks, faces for room editors, vehicles, usernames (So you know if it's a troll), area's the room owner can specify only certain people can edit, so they can have houses, etc., there should be bricks where you need a certain amount of blue/orange coins to go through, the room owner should be able to ban people from their games,weapons, there should be game types (Like one with only weapons, one with only vehicles, etc.), slanted arrows (Up-left, Up-right, Down-left, Down-right...), Aand a save map code thing- where you can copy a map code, come back later, make a new map, and paste the map code and you have the saved map, like on Free Rider 2.
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