CargoCruz
My concept differs radically from yours, Mr. Holz!
Your initial concept, sketched atop a Silvio V1, seems too complex to me.
In my opinion, Cruzbike frames are well engineered.
Logically, as the frames are already built and field-tested... I'd mount my load-carrying
modifications to the existing frames and save both time and money.
If I wanted a load-carrying Sofrider, the model I own, I would:
-keep the frame, wheels, swing arm and front end.
Why?
They work, they're already built and I don't need to reinvent them.
-I'd remove the seat... and replace it with a monocoque, aerodynamic,
one-piece combination of tail-trunk and panniers.
This would bolt on in place of the original seat pan;
the original fabric covered foam seat pads would be reused
on the monocoque cargo unit.
-I might replace the stock shock with a more robust unit, if needed.
The advantage of a bolt-on monocoque cargo carrier is that
it can be removed and replaced with the stock seat, quickly restoring
the utility of the stock bicycle.
I can see that this would be a less flexible solution than hanging
different-sized bags on a scaffold would be,
...but in my mind's eye, it would be much more elegant!
-Steve