> Mars won't be a powerhouse of industry, commerce, or culture; at best there will be some modest scientific output. It's a tomb world.
I wouldn't go that far. Yeah, the habitability sucks, but it does have plenty of natural resources. Combined with the low gravity, I suspect it could be a useful manufacturing and refueling hub, especially as a pit stop on the way to the outer planets.
That said, I think Ceres is a bit more viable for that, due to closer proximity to the asteroid belt (since it's in the asteroid belt) and due to it being a giant ball of water ice and hydrocarbons (water and hydrocarbons being pretty crucial for both refueling operations and human colonization). If the gravity on Ceres ends up being too low for human comfort, that just makes it easier to build centrifuge habitats, be it on the surface or in orbit.