Anderton
I could not agree more!! And, excellent suggestion about MIDI only at first. Also, the audio tracks could be MP3 or Ogg Vorbis. After all, it's not going to be released on polyvinyl records...
I know of established companies that use Dropbox, Google Drive, and the like to host their downloads. Image Line uses Google Drive as one of their hosts for FL Studio downloads. File hosting can be free or cheap, so that doesn't seem like it should be a barrier.