An intruiging idea. I think a lot of it would apply well to Mars as well - no reason you couldn't have aeroponics everywhere there too, given nuclear power or vast solar arrays for the lighting. Create a large football-stadium style dome and you've got a great park if you want "open air", and of course there would likely eventually be large inflated (or glasslike) domes for farming radiation-resistant plants,
As for opressiveness, once a wall is opaque, you can't really perceive how thick it is. And I'm not sure how attractive Venus would be in comparison - sure, you may get a lot more windows, but if you're hovering at an altitude for Earthlike conditions, you're roughly in the middle of the cloud layer, so visibility will be limited to gaps between clouds. It would be great if you could float just above them, but at that altitude you're down to about -70C ambient temperature and less than 1/10atm. Not exactly conductive to a balloon city.
There's also those ever-present lightning storms all around you - that's going to be noisy, and a serious maintenance issue. I like a good thunderstorm probably more than most, but I don't want to live in the middle of one 24-7. And how do you plan to prevent lightning strikes through your habitat? An ion shield such as trees commonly deploy might help, but that's going to be a lot to create and maintain, and isn't 100% effective, so you'll still have to regularly patch large scorch holes and any equipment that gets hit. There's a reason aircraft strive to avoid thunderstorms.
That also brings up an issue with solar panels - not only will their conductive components tend to act as lightning rods (intercloud lightning travels horizontally as easily as vertically), but since you're in the middle of the cloud layer they won't actually be getting anywhere near as much sunlight as they would in orbit, maybe not even as much as they would on Earth or Mars, after all there's no such thing as a clear day on Venus. I don't suppose you know how opaque the Venusian cloud layers are? I imagine the probes would have offered a fairly accurate assessment. And while you could float solar panels above the clouds easily enough, the steep wind shear with altitude means you couldn't keep them tethered to your city (even if stringing miles of electrical cable through a thunderstorm wasn't a really bad idea to begin with)
Also, one other point to consider, is what would the actual radiation exposure be? If the ambient pressure is ~1atm, then you have roughly as much air above you as you would on Earth, but without a magnetosphere you're going to be counting on that air to block a lot more radiation. Especially since the solar bombardment portion will be 80% higher than on Earth, and 4.4x times higher than Mars. Of course that's mostly solar wind, whose relatively low-energy charged particles should mostly be rapidly stopped by atmospheric collisions. It's the cosmic rays that are the real issue.