It's also important to acknowledge how times have changed. A lot of the skins I posted were actually made a year or so earlier than what the publish date alludes to.
I never took it so seriously as to study those sorts of details... I also didn't attempt to advertise myself whatsoever back then. I did it all for fun, and figured that, although my skins weren't anything professional, they were at least decent. I noticed other "decent" skins receiving a lot more attention, and just wondered what I was doing wrong that could be an easy fix.
If I get back into it, I'll be sure to follow your advice :)