Let me start off by saying that I know that bast is slowing down on the content and I fully support that. This idea is just me not having enough to do during the work hours.
So, for this map idea, I'm thinking a similar concept as the waterworld map, except the non-buildable areas are empty space and the buildable areas are metal platforms that can be deconstructed and constructed by basic rovers. Atmosphere should require storage on this map in order to keep increasing, and the map can never be terraformed. I would add ice patches on the platforms to give a starting source of water until the below mentioned grinder can be built.
The main challenge to this map is that you have no resource nodes. In order to get resources you have to chip away at the very platforms that you are building on. Each platform square gives you ore, but since platforms in each map generate abundantly but are still finite, you need a way to get more ore.
Queue the ore mass fabricator(mf for short). A basic mf would take 100 power and would use it to generate orethrough the process of turning energy into matter, albeit slowly. In order to get a good amount of ore production, you would need to build tons of solar panels. In fact, this map will be all about solar panels until you are able to get more complex resources like oil, uranium, and eventually build power towers. More complex mf's and solar panels should be added as well to scale with the colony, but really, all of these mf's should only be allowed on this map, as they might break the game on other maps.
A basic gold mf would also be needed and would take 150 power to generate at a slow rate. A gold synthesis lab would be able to produce more gold later on.
Another structure called a power transport beam would produce money by consuming 1000 power and water. The principal behind this structure is that it beams power to another site and that power is used by customers who pay you and it needs water to keep from melting down. More complex machines like this could be added to produce higher amounts of money. After all, the whole point of a dyson sphere is to make tons of money by collecting as much solar energy from a star as possible.
Condensed air canisters should be added to provide atmosphere storage and would be made from steel. another greater version should be added as well to provide more atmosphere in late-game. The purpose of this is to allow atmo condensers to produce water instead of having to develop more water buildings, and terraformers would act as suppliers to the condensers rather than terraformation machines. It would also be interesting of colonists on this map actually consumed atmosphere. That could actually be a regular thing on all maps that start with no atmosphere.
An ore grinder would grind ore and steel into regolith, which would be needed for water production early game through the use of regular extractors.
Another way to get wood would be required as well, since it is needed in order to get oil, plastic, and sugar. Perhaps a forestry dome would work, acting sort of like a tall hydroponic just for trees. Or maybe a cellulose fabrication lab that takes food and water and turns it into a wood-like substance comprised of cellulose. Or, if the power beam was implemented, the colony would be making plenty enough money to keep a good amount of wood at all times.
Finally, an atmospheric shield generator should be implemented mid-late game to allow for earth-like atmosphere buildings to be built inside it's radius. If the shield shuts off, those buildings deactivate. This would be good for tourism and outdoor entertainment like restaurants, stadiums, and hotel resorts.
After building a good supply of ore and gold fabricators, progress should be the same, albeit the colony would need to continue to rely on mf's for ore during the entire playthrough and would need to buy certain higher tier resources like alien arts and the like.
Well that's all for this idea. I'll update if I get any more. Let me know what you think.