You need to give us more. I feel that just the heat is a tricky problem, even at 50km altitude. Anything todo with Venus is very much scifi at the moment. It might be easier than a moon base but we can not know.
Oh it wouldn't be easier than a moon base or simple orbital habitats. And as for Venus being scifi, anything to do with space colonization period is scifi right now; humans haven't even stepped foot on another celestial body of any kind in over half a century.
Rather my meaning was that it's (a little shockingly) the best suited planet for humans in terms of most closely and reliably resembling conditions humans could survive in, which relates to the terraforming notions I was replying to.
It'd be overwhelmingly harder to make all of Venus Earthlike than to just use the existing relatively Earthlike regions of the upper atmosphere to our advantage along with their unique properties. Cool off Venus and you just get a big ocean of liquid or frozen co2 to have to deal with after a loooong time and a lot of construction. Keep it like it is and a fraction of the resources/effort will yield far more utility while we can still enjoy a segment of the atmosphere.
Isaac Arthur on YouTube makes videos on sci-fi ideas that we might be able to do within the laws of physics, albeit not with today's technology. He did a video on Colonizing Venus some years ago, and an updated one a few months ago, and some others around colonisation and teraforming of the planets in the Solar System: