As we know the victories are a little shallow and there are features from civ5 BNW that aren't used in BE. I suggest that aspects of the BNW culture victory should be used in the Promised land victory. Tourism in BNW represents the esteem felt for another civilization. In BE it is just assumed everyone would want off earth to where ever you can go and the Emancipation victory reinforces that by suggesting that taking over earth to remake in in the image of supremacy is an act of mercy. Narratively that works but I think gameplay wise it might be more interesting if it took more convincing to get people to abandon the hell-scape of Earth for the unknown of an alien planet. The devil you know beats the devil you don't. Something I've noticed is that the dome and terrascape, both of which are used to create earth-like environments give culture and Purity also gets the Terra vault building and the holomatrix orbital, also gaining more culture. The other affinities have there own culture boosters but purity seems to have a slight extra focus. I would suggest that purity should have to prove the viability of living on an alien world to earthlings. Their cultural output representing the general quality of life on the planet and enhanced with domes and terrascapes that have a distinct earth-like appeal. A tourism like system could be used to measure the desire to relocate to the new planet. Also, currently you can place them on snow and they're fine. I'd also suggest that the earthling settlements have some needs to them. Currently they allow stacking of six in one settlement. I'd suggest that that number be based on the tile yields of the area or from trade routes. So to stack a large number of earthlings you'd either need a good location (thus not using it for a productive city), a location made good with terrascapes, or trade routes to the settlement. The settlements would function for their own good but not for the betterment of the colony at large. I would though still have cultural improvements around settlements contribute so they can add to the culture needed to attract more earthlings. Obviously this is too much for a patch and it would have to come along with improvements to the other victories, but it makes the promised land more like the building of a new earth than just dumping earth losers onto an iceberg like it is now.