Hello David

> So would buffered mults work in the same way but with no risk

No buffered mults wouldn't work at all. They are the opposite of a mixer
(think them as 7 aux sends of a mixer, with send volume turned fully up).

A mixer is a mixer. Thats it.

A multiple in your planned setup is simply a shortcut between two
outputs and one or several inputs. Using them may work some way, as long
as you are feeding them with the outputs of equal modules. Feeding them
with the outputs of different modules may cause troubles; but as long as
they are built like Doepfer ones (a serial resistor in the output path),
you won't kill them. The troubles may be in the dimension of "one signal
suppresses the other signal in a significant way" or "signal A causes a
frequency damping of signal B". This may be fun or may be an unwanted
effect.

Florian