Thanks for the post! I'm using the xc-16-50 with the same results as my prime lenses, and have the same conclusions as you.
Now i'm trying to be a better photographer looking for better light and composition instead of buying lenses.
I was looking for something a little wider than my X100T and X-T1 with the 18-135. I didn't want a wide-angle prime and didn't want the expense/no OIS/size/weight of the XF 16-55, so bought a used XC 16-50 for $199 including hood and caps, in "like-new minus" condition in KEH's rating system. I thought it might serve for occasional use when I wanted the 16mm length, but was pleasantly surprised to find this little guy is a very nice lens in general once you get past the plastic and lack of switches and aperture ring. I believe it is substantially better in every way except build quality than the 18-55 I sold when I got the 18-135. The sharpness and color/contrast for landscape work is outstanding, and the OIS seems to work very well. I don't see much in the way of comment about this lens; maybe everybody who got it as a kit lens sold theirs?
Dick