I like your Idea! That would be the ideal modular platform.

But if we're going the ethernet route why not Ravenna? It's open standard I think.

Wouldn't there be a possibility to implement DSP or even Jack in Ravenna?
Consoles from Lawo are Linux based and use Ravenna.

Just some quick thoughts.

I just remembered that we had a discussion about Ravenna here before, I think the conclusion was that it's not that simple...