Gallery in https://krita.org/en/features/gallery not updated for a long time.
2018:
2019:
I think need to add a "Artworks of the Month" in Gallery.
Artworks will be choose from Reddit, Twitter, and KDE's Community Krita Gallery.
Every month will published in Gallery the best artworks created in Krita.
Need to come up how the best artworks will be chosen, the artworks with the most likes from Reddit, Twitter, and KDE's Community Krita Gallery, or create a special tag.
For example - #KritaMonthly, peoples will publish their artworks with this tag and among them will be choose the best 5-10 artworks and will be published in https://krita.org/en/features/gallery.
References:
https://www.clipstudio.net/en/gallery - Illustration contests on different themes
https://medibangpaint.com/en/pc/gallery - On the bottom have a mini twitter
https://www.painterartist.com/en/product/painter/#gallery - Have a tags (Concept Arts, Illustrations, etc.)