I guess it depends on the scale of regime I'd have. Once all the normal stuff happens and people have housing, good jobs, transit, food, healthcare, literacy, half the earth rewilded, and everything else, I'd go buckwild.
We're gonna set up Mars for terraforming. Put a big fuckoff magnet at L1, and put a particle accelerator on Phobos to create a torus of plasma along its orbit, do 'em both, we need a backup because this shit has to last a billion years. Smack it with some ammonia-rich asteroids, shotgun the surface with extremophile lichens and bacteria, build some ecopoiesis domes. Just let it go wild. Not a colonization attempt, just create a trickle of progress and let it slowly improve over time and go wild til we're actually ready to do something with it.
We're going to learn everything we can and we'll save all of our knowledge. We will learn everything we can, uncover old mysteries, and explore. The only limiting factor for sciences should be people-hours. And we're going to make backups. Off-site ones too, maybe even off-world. We should never forget anything ever again.
We're going to preserve languages and learn a universal second language. Teach everyone Esperanto or something, but make sure that people's native languages are preserved and retained. The Sapir-Whorf hypothesis may be bullshit, but I think there's a lot of cultural value in preserving languages. It'd be great for everyone to be able to communicate together, but it's important that we're not losing things along the way to that goal.