Fewer then 360px are considered to small (LINK).
So something takes longer to update then it should or there might be another bug. I think you already posted a similar bug report.
Personally, I aim to get 1000 or 1200 pixel, the vast majority of those 3000+ smartphone pictures are a waste of server space in my opinion (you would need a very good optic and sensor to justify such a resolution).
For your pictures I would try to get as near as possible to a top down few because they are shot at a slight angle. This is especially visible on the 10 kronur pictures that they aren't circular but oval.
If you have nothing else the old coffee mug technique is better then free handing.
