In a similar position too can't decide on size. I tried an AW10 42mm and this is what it looks like. One picture is looking down at the watch on my wrist and the other is holding my hand on my stomach towards a mirror and taking a picture in the mirror. The first picture looks good but then I think it looks small in the second picture. Wrist size is 15.5cm. I've seen a few videos on YouTube which indicate this is this right size for my wrist. I also prefer a smaller device as this is my first watch.
View attachment 2548238