I have a feeling that many Matomo users aren't aware of the fact that if they dislike a part of the design of Matomo, they can write a very basic theme that overwrites the css/less and with little effort can publish it on the Marketplace for everyone to use.

At the moment, themes are quite hidden. Especially the management of themes is hidden behind a small link in the header of the plugin management.

I am not sure where to link instead, but maybe even a separate menu item for themes could be added.