My biggest issue with QEMU is trying to keep up with seemingly arbitrary changes to the command-line options format over time, and keeping up scripts that can launch an image across different versions for testing.

Originally if you wanted e.g. a SoundBlaster16 device you could use -device sb16. Then it changed to -soundhw sb16. And now it's -audio driver=none,model=sb16; this has been happening with several different classes of options over the years and I haven't found any good documentation of all the differences in one place. If anyone knows, I'd appreciate it.