I'm somewhat relieved to know I'm not the craziest of all, by way of wanting doubles of every module.
I will say--in modest seriousness--that a third JF outside of a dedicated Mannequins system is an incredibly sensible thing. In my unscientific survey of the more common EG/function generators available today, nothing offers as many channels with as much flexibility in the same or less hp than a JF. And that's looking at it just as a fairly conventional EG/FG, entirely aside from its sound generation capabilities.
A bargain actually, I dare say.