I can’t speak well enough of qTractor: it has a nice and intuitive UI, it does MIDI and Audio, it supports many different plugin formats, both instruments and effects (VST 2/3, LADSPA, DSSI, LV2), and it supports many forms of audio manipulation including time stretching and pitch shifting. If you’re looking for an open source DAW in my opinion it’s the way to go https://qtractor.sourceforge.io/