There is really no way to wrangle the format of "forum" software to provide the kind of display and organization that we would want. It's really just not the right tool for the right job.
Forum software by it's nature is chronological in order, and is organized in threads of posts that while they can have a Subject line, can't have any "preview image" or any other way for folks to just scroll through a "gallery" of skins that have been attached. It's really not a good way to "browse" or even "search for" a skin that appeals to you.
I think the "Share Your Creations" forum area is very useful, and I encourage folks to create posts with attached images and links to their completed .rmskin creations for the community to share, but it's a far cry from what is needed to properly support the many, many thousands of skins that are out there.
In any case, we really just don't have the storage space to encourage ALL the skins out there to be attached to posts in the forums or otherwise uploaded to our site. Our available space is measured in a low-order number of Gigabytes, and we have already had to go hat-in-hand to The Open Source Lab at Oregon State University asking for a bit more space in order to support the boatloads of images that are attached to posts. There is a limit to what they are going to want to provide.
There are some limits on the size of an individual attachment that is both a function of our wanting to keep space usage under some control, and also a limitation of the normal setting for the underlying PHP infrastructure that runs the software. That is currently at 10 Megabytes per attachment, and we would be hesitant to increase that by much. If you want to provide a download of a .rmksin larger than that, you need to do it as a "link" to someplace you are hosting it.
In my view deviantART continues to be the best alternative for a central place to host the community's skins for sharing. The new interface has added some challenges to this, but if we all get in the habit of "tagging" submissions properly, in some consistent fashion, it can make browsing and searching for skins there almost as easy and effective as it use to be. For instance, if EVERY skin that was submitted there was "tagged" with "rainmeter" and ".rmskin" at a minimum, with additional optional tags like "weather" or "clock" or whatever, then users could pretty easily find just skins, by searching for "rainmeter" and ".rmskin", while not getting the boatload of images of desktops and other assorted "art" that isn't what you had in mind when looking for the latest or greatest skin for your needs.
I currently hit the site with https://www.deviantart.com/search/deviations?order=most-recent&q=rainmeter, which isn't perfect, but gets me in the ballpark. I get a lot of "images" as well as "skins", and they can be hard to distinguish at first glance. If all submissions were tagged with ".rmkin" as well, that would really help. Just not sure there is a good way to get this advice out to the rest of the Rainmeter world that isn't active on these forums, and I doubt much could be done about the huge number of skins that are already there. A great many of those authors are no longer even around.