Yeah definitely it is the less boring one of the 3. It's got a few options so I'll play around with some wire and thin it out a little.
No idea about sikkimensis, presumably it is the same thing.
And nerifolia is not what any of these are either, nerifolia is an Asian species and distinctly different as is salicifolia which it's often called too but that's an AFrican species.
Most willow leaf figs are F. salicaria and there origin is unknown. Back on page 3 of this thread there is a little history about them.
I'll have to wait and see if the cuttings strike but I'll keep it in mind for sure.