Hello, i have a little suggestion regarding the non-metal bands accepted in metal-archives based on the side-projects rule.
Since the webpage is metal-archives.com and i know that those bands wont be removed and they will persist on here i suggest beside the Genre(s) on the non-metal bands to add a little note like (Side-project) by clicking on it another page will open explaining the side-project rule like that the newbie users wont get confused when they see a rock/ambient/noise... band added in the webpage and it will be better for regulars.
What do you think?

Yes, Morrigan was already speaking about the possibility to create a special section for such bands in the new version of the Metal Archives.

Something like what you propose should be the minimum, if the side projects will be kept here in such a large number in the future.
You should change the topic name to "side projects listing" or something like that, because it is not clear from the first look on the topic, what exactly you mean.

One small question regarding the side-project-rule of non-metal bands.

http://www.metal-archives.com/band.php?id=22384

There is an additional site-project called "Where Rivers End", if there will be a release will this band be added, too, or is the site-project-rule only applied when it is one of a metal band? There is no release currently, only one track on a sampler, but from what I know they are currently working on a release. The music is not metal, but mere folk.

If he is still active in the metal bands - he plays kantele in at least two doom/folk metal bands, then it can be seen as a side project of metal musician, but the release has to be on a label, which is able to distribute worldwide.

He seems to play only in bands that have only two or so releases. It seems he is more of a guest in a few of their releases than a full-time member. So as far as I know, his sideprojects are the metal bands, not the other way around.