I think your system is geared for large production, like graywolfs. Passive is great for small producers and active is just too much of a buy in. The fact that yours, and similar systems are expandable is a smart move. :) And no, I would not say your system is a copy of anything. Sure the idea behind it isn't new, but what usually is in life? It comes down to applying it better than others!
I do think the designs I've seen (yours, graywolfs, tamisium) are all good for the segment they serve. I would think that an automated 8oz unit would be more advantageous than the same sized passive system tamisium makes.