Im still suggesting my rho shape variant of this idea. You have a straight runway with enough distance to land but then have the circle for slowing down once landed.
That won't work. Normal small airports that only have one runway use the runway in both directions, depending on wind direction. You never land with a tailwind, and you never take off with one either. A rho shape wouldn't work here because the circle is only at one end, preventing bidirectional use.
I don't see how. I don't see how this would result in better land utilization at all. You could have a big circle around the airport (like in the original circular runway idea), with a bunch of straight "stems" protruding in all directions, which can then be chosen based on prevailing winds. Then airplanes can land on these stems and then enter the circle after their speed has greatly dropped, so it's really like a big circular taxiway of sorts. And departing planes can accelerate in the circle some, then proceed onto the appropriate stem and increase to take-off speed and take off. This might actually increase throughput, I dunno. However the land usage would be atrocious, because you probably aren't going to have any productive use of all that land between the stems, and the overall area used when you account for the maximum extent of the stems is going to be enormous. The traditional layout of having a number of parallel runways really makes more sense as far as land-use efficiency.