My builds depend a lot on the M-income situation and the purpose of the Habitat.
For Organics:
Industrial habitats:
When I have a rather limited amount available, I'll go 3 Housing + 5 Trade to create more or less self-sufficient Habitats.
Under regular circumstances I'll go for a 4-4 split, which unlocks plenty of building slots and only needs marginal special resource investment to employ all pops.
If I am swimming in M, I'll go with 5-3 and put down multiple maxed out alloy plants
Military Habitats:
3 Housing + 5 Trade, this way I have enough jobs even when most slots are filled with forts.
Science Habitats:
3 Housing + 5 Research, although I rarely use them, since I tend to rely on planets for science.
For Organics:
Industrial habitats:
When I have a rather limited amount available, I'll go 3 Housing + 5 Trade to create more or less self-sufficient Habitats.
Under regular circumstances I'll go for a 4-4 split, which unlocks plenty of building slots and only needs marginal special resource investment to employ all pops.
If I am swimming in M, I'll go with 5-3 and put down multiple maxed out alloy plants
Military Habitats:
3 Housing + 5 Trade, this way I have enough jobs even when most slots are filled with forts.
Science Habitats:
3 Housing + 5 Research, although I rarely use them, since I tend to rely on planets for science.