After a period of silence, @Reisyukaku has shared what some would call a rather unexpected project with the community. What you see in the picture above isn't just a custom theme, but rather a homebrew replacement of the Switch's home menu.
The project is called ΔLaunch (DeltaLaunch) and the developer stresses it's very much a work in progress with no ETA yet, so it should be taken just as a proof of concept for the moment. It works by replacing the OS's qlaunch process, which controls the system settings, news and home menu applets. The result is an open source menu replacement which can be customized completely. Themes can reportedly be installed by editing an INI file on the microSD card, which supports all the things you'd expect from a more traditional Switch theme (changing the background, editing the layout, etc.) however it will do away with custom theme formats as it will instead simply load resources from a directory specified in the aforementioned INI. It will also be independent from the firmware version, meaning you won't have to worry about custom themes working only for specific versions or having to reinstall them after an update. Finally, there will also be support for adding more icons on the home itself (notice the browser icon near the news' one)
Rei has also posted a brief video showing the homebrew in action:
While, as previously stated, the homebrew is "far from done", it could be something worth looking forward to if you like to customize your Switch's home menu appearence.
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