Varonha Frameworks winter bike / FW Evans 650b conversion rat bike fun

but are big, heavy things so not ideal either

as stealthy black as possible and preferably available in budget and fancypants options so I can run the same shape on this and the Saffron.

By 'fancypants' what I really mean is lightweight.
One Rolls is roughly equivalent to two (not even particularly weeny) modern saddles.
This bike is already pretty weighed-down by the guards, dynamo stuff and groupset... And ideally I would have the same perch on the Saffron, which will be an out-and-out road bike.

Shame they haven't updated the Rolls (since the Due) in the same way as the Regal and the Flite.