[toast0]

If you're willing to forgo Linux, but want to be Linux adjacent, maybe look at getting the Linux hda drivers running on FreeBSD linuxkpi; HDMI audio on at least intel would work better with coordination between the audio driver and the video driver; FreeBSD uses Linux drivers for video, but not for audio and the coordination is missed, so the audio driver doesn't know when the video driver has reprogrammed the clocks for a different resolution and you get mistimed audio :(. Alternatively, figure out how to use the coordination hooks in the Linux video driver with the FreeBSD audio driver.

But really, to answer your question; the best thing is to find something that you actually want your computer to do that's feasible, but not possible because there's no kernel module. Then you'll be incentivized to keep going with the project, not just a resume/interview material project.