

MuseScore is the best! I’ve come from Sibelius and Dorico, but the ease of MuseScore blows them away for most use cases.
For mixing, I regularly use several plugins from Airwindows, namely TapeHack, Distortion, Flutter2, Srsly2, among others. ChowDSP is also a great FOSS plugin developer. And while Reaper isn’t open source, its JSFX are, and so many of those are rad.
You may like to check out Ardour. I haven’t used it, but the Ardour users I’ve come across seem to be quite happy with it.
I’d recommend starting with Airwindows Consolidated then. It’s a multi-FX browser for Airwindows with a prettier GUI. https://github.com/baconpaul/airwin2rack/blob/main/doc/manualdaw.md