Robust still gives you perfectly habitable Habitats without Voidborne, so you've got that going for you, which is nice.
My advice for a Life-Seeded start using some Habitats would be:
- If you have a bunch of 2-size Energy and Minerals deposits, build a Habitat over them, and move your Energy and Minerals to space.
- If you have a bunch of small Research deposits, build a Habitat over them, and build only Research districts (and a Habitation district which later becomes another Research district) on these habitats, plus one Holo Theater building.
- If you build a Habitat over a Rare resource deposit, you will be able to build a number of rare-resource-mining buildings equal to the deposit size. E.g. if you find a 2-size Exotic Gases deposit, you will be able to build 2 Gas Extractor buildings on a habitat. This is more useful for someone with the Voidborne perk because you'll often find 5-size rare deposits on a Precursor system, but you usally need Voidborne to have 5 building slots early.
- With Voidborne, the other great use for a Habitat is as a Refinery. What you do is build 2 habitation districts and 2 leisure districts, then make all the building slots into crystal / gas / mote refineries. Without Voidborne you might not have enough building slots for this to be profitable early, but later it's quite viable.
Habitats will grow pops if you have a ton of housing, but that hurts sometimes (e.g. personally I want 12 Researcher jobs rather than 6 jobs + pop growth), so I'll move pops into those Research habitats instead of trying to use that habitat to grow and research. With your Bio Ascension, though, you can plop a Clone Vat in those non-growth Habitats and grow there anyway, albeit at a high food cost.
If you have a spare Habitat building slot, you can plop a Hydroponics building, too.
Use your Starbases to offset that high food cost by plopping a Hydroponics building whenever you have a spare slot, which in my experience is quite often.
Now your Gaia homeworld can turn those Mining and Generator districts into Agriculture and Industry, with fewer Agriculture needed as you get more starbases upgraded.
With even just a handful of Habitats, you should be able to specialize your capital a bit, and 2 full Research Habitats ought to take you far enough that you can either get Gladular Acclimation to remove your Gaia preference and colonize whatever planets you find nearby, or Climate Restoration and then the World Shaper perk so you can spam Gaia planets.
Probably not an optimal usage of Robust but it does work.
