My home-made stands have a bit of tilt built in as I had a pair of stands for smaller speakers that also have a tilt and I liked that. I have a few half baked theories about why which I won't share for fear of embarrassing myself :)
I still manage to use the tops of the speakers for some objects but a plant pot might be a bit too much.
PMC are doing the trapezoid boxes at the moment. I don't like the look so much. I like the last one on your list but I don't know anything about the inside of the boxes and what implications that shape has.
Like you I think the last option (second image) is best. Kind of reduces the visual and physical intrusion into the room. Parallel opposite sides aren't ideal, but I think acute / obtuse angles are better than 90º. Anything is better than a rectangular box basically!
My home-made stands have a bit of tilt built in as I had a pair of stands for smaller speakers that also have a tilt and I liked that. I have a few half baked theories about why which I won't share for fear of embarrassing myself :)
I still manage to use the tops of the speakers for some objects but a plant pot might be a bit too much.
PMC are doing the trapezoid boxes at the moment. I don't like the look so much. I like the last one on your list but I don't know anything about the inside of the boxes and what implications that shape has.