Right now in Humankind there's the well known feature of ascending your current culture, where you don't get any new culture bonuses for the next era but your fame score increases, since you decided to remain as an older culture that doesn't provide anything new. Well, what if you had the option of doing the opposite?

The idea is that on the culture screen, you'd be able to look at and pick future cultures from beyond the next era, say picking the British during the ancient era. They would have era appropriate architecture and since you've chosen you want to be the British in advance, other players can't pick them even if they reach the industrial era before you. However, the British have no ancient era bonuses, so instead you receive bonus fame until you finally reach the era the British are in at which point you finally get their bonuses and stop receiving bonus fame.

This is rather sudden thought and very imbalanced idea, as well as one that might take the fun out of the game, since choosing cultures or racing for specific ones is a large part of the fun in humankind. Still it might make for an interesting mode, and let you see more comical things like Brazilian knights in the 9th century.