Simply, a new biome could be the City World (Ecumenopolis means a city that entirely encompasses a planet; Earths possible future as theorized), one which would have huge buildings and very, very deep 'under city' style bowels. Each race could have their own style of city world, except the Florans because cities just aren't their thing, are they? Basically, it would be like those city worlds from the Star Wars saga; Massively tall buildings where the more important society members live and then a mid ground where the 'streets' are, patrolled constantly by guards, ships, and mechs, and then a seedy underground slum or ghetto in the systems below the city where the generators and shield projectors are and the access tunnels to the sewer systems (already a dungeon), and then a really old and ruined city beneath filled with criminals and the few native animals that survived the conversion. They've already half-created this with pure dungeon worlds, so it would kind of work. Some of them would also be like Outposts, neutral cities where races can co-exist as they trade and travel. It could also add some new features to the game, like a place to dock your ship and repair it or add weapons or expand or whatever. It might have new buildings like Senates, Bars, Hotels, Factories, etc. and maybe it would have the orbital defense artillery I spoke of in This suggestion thread for Invasions. City Worlds would be much less common than any other worlds and belong to specific factions if not neutral, and all would have shield generators somewhere around. Another idea that would work well for this would FINALLY to add each races homeworld. They would probably be these Ecumenopolis', and like I said each would have their own style. They would also have a shield generator hidden somewhere like where players can't get it, so that they can't destroy the whole world and save the Grounded Avians. They would probably be hostile to outsiders, and in the case of the Hylotl and Humans who have no homeworld they would have their own temporary Capitol Ecumenopolis'. All but Florans, who would have a huge forest on their home. Obviously it would be very dangerous for some to return to their homeworld, but not for all like the homeless humans. Leave a like, reply, and check out my other threads (but only the good ones. I phuqued up on some.)