Personally, I use MorphOS because it's light weight on the old PPC Hardware (Very Quick Bootup), things that didn't run well in MacOS runs much better (I can run videos in 720p MKV in MorphOS which I couldn't do in OSX Leopard on my Mini). I usually run some 68k apps for productivity like wordsworth,
From what I understand, SoundBankster can be used for some DAW stuff. It is disk-jockey software, it allows mixing, syncing, tone correction, etc.
if you have a knack for programming, MorphOS is always looking for new software, namely stuff to connect it to the outside world really, support for MS office stuff is a big one. Open Office isn't on MorphOS, but someone ported it to OS/2...