Oh, I don’t know, I think you’ve got a pretty technical crowd here, and I’m sure the setting would be understood a lot more than a ‘buffer to the power of two’ 
How about ‘make master clock when grouped’ or something. Or ‘group clock priority (1,2,3)’
But yeah, I get that it’s a lot of effort and possibly little benefit. Still, if it were available one day I’d use it - I’d much rather keep the lounge hifi running its best when grouped, and have the raspberry pi’s and kitchen speakers ‘messed with’. Don’t let it hold you back incorporating other DSP like room correction though 
I guess you’d also be a bit stuck if the master disappeared, although I guess that’s the same now with your auto-designated device.
As always it’s great to know you guys think about all this stuff… I would never even have been aware, but now I am…