[rbanffy]

Keeping the habitat 50 Km from the surface for decades isn't a trivial task.

Mars also has easily accessible water and a lower gravity. All you can get from Venusian high atmosphere are the gases you capture. On Mars you can mow rocks to get stuff like, say, steel.

[InclinedPlane]

Indeed, there's not a lot to recommend a Venusian floating habitat over a pure space station, for example.

However, if you look at what's possible with Mars, things get interesting quickly. Firstly, the CO2 atmosphere and local sub-surface water ice can be used to generate rocket fuel with a very low level of infrastructure, making initial exploration dramatically more efficient. Secondly, Mars has plenty of Sun and near-Earth day/night cycle, making it straightforward to grow food there. The day/night cycle also makes relying on solar power much more feasible, and makes direct communication with Earth more reasonable (since a location on Mars and on Earth will generally have line-of-sight to each other on the order of once per day). Thirdly, local martian materials can be used to maintain a self-sufficient industrialized civilization over an indefinite period of time (local metal ores, water ice, CO2, even Uranium ores, ability to grow food, etc.)

[rbanffy]

Doing some fact checking, you could build automated processing stations on Venus that could process atmospheric CO2 and water vapor (the former is most of Venusian atmosphere and the latter about 20 ppm) into methane and O2. There is plenty of sunlight as a power source too and an abundant source of heat. The gravity well is much worse than the one you find on Mars, but, as far as an automated facility goes, it's conceivable just to leave it there for decades, let it fill itself to its full capacity over decades and just ship a couple tanks coupled to engines to low orbit (or a cycler one) where a passing spacecraft could pick them up. The empty vehicle could then return to Venus and start its cycle again.

Mars is easier, but there is a lot of Carbon on Venus and it would be nice to be able to ship it elsewhere. Maybe then we could somewhat reduce the greenhouse effect and make it more comfortable over a couple hundred thousand years.