The first two are the ones that grab me, also. On the second one, I'd cropt that black line off the right and I agree that I would like to see it lightened a little.
On the first one, I would crop it square. The main focus is that wonderful beam of sunlight, but it's a little lost in the size of the image. The columns act as a framing device, but there's still some image left outside that frame. You could come in on each side and still have the columns frame, but the sunbeam would have more prominence.
Really nice work!