I am by no means a developer so what I think does not matter that much since I couldn't help developing it.
If we can somehow confirm that whenever there is a Master, there is also a PCM, and selecting PCM does not reduce any functionality, then we could just hard code PCM (and Front) and be done with it. Sometimes, the less options there are, the better for the normal user. That's why I was trying to get feedback from people using Master, as Master will not work for me on any PCs I tried, and if all of you guys use receivers for your sound, it's possible that Master has no use at all?
Of course it would be nice to put the option in the sound card, but like you said, it requires to create a standard sound card template which might be a lot of work when there is a simpler solution that suits most? (and we can use the developer's time to do some more usefull things?)