I think the Barrel on the purple background is warmer and tends to highlight the details of the watch. This is how I would like to present my wearable collection. The last photo of the Tonneau on white background is sharp and clean. This is how I would like to present watches for sale to increase interest and price.
The green gold on purple seems a bit dark but the white Waltham on white almost looks washed out. All the photos could be touched up in post processing if need be but I am not at that level of photographic skill. It seems as if a white background is better for yellow or green cases and a dark background is better for white cases, for me anyway.
I agree on all points! The two photos were originally adjusted differently in the computer (brightness, contrast, etc.), so I was trying to even them out, so to speak, but my over-zealousness at the computer got the better of me and that's why the second photo does look washed out
Sometimes, less is more!
I really do like to tweak the photos. Compare a white cased watch with an AGN dial with a green cased watch with a black enamel print dial, you have to adjust them differently so they can look as good as possible. The object is to digitally enhance and not disguise, change or otherwise try to hide some detail of the watch. That's why with so many Ebay photos, a favorite ruse of the "less than reputable" sellers is to take the photos with a flash. Ya can't see scratches on a case with the reflection of the flash
As far as the skills required to properly digitally enhance photos go, it's really just a matter of what looks good to your eye, just like you said. The mechanics can be learned in a very short time.