CO2 has carbon in it. Strip off the oxygen to breathe, the rest makes very strong building material.
Attach hydrogen, you get rocket fuel. Or plastic. Bind in some nitrogen, you can have proteins. There is probably silane lower down; send down a balloon to collect it, for silicon. Or all the way to the surface, to collect rocks.
Nuke power is totally practical there; no shielding needed, or worry about leaks; you just hang it a mile below your living-space balloons.
Attach hydrogen, you get rocket fuel. Or plastic. Bind in some nitrogen, you can have proteins. There is probably silane lower down; send down a balloon to collect it, for silicon. Or all the way to the surface, to collect rocks.
Nuke power is totally practical there; no shielding needed, or worry about leaks; you just hang it a mile below your living-space balloons.