AF pilot unions have always refused the "distinct chain of command, Captain > Senior First Officer > Junior First Officer" as this would mean less trained/less qualified (read : less paid) "junior F/O".
What about Captain / Senior First Officer / First Officer ?
Surely this means a special training for LHS qualification including ground school, sim training, line training with checkout as Senior First Officer.
And yes, pay is inbetween First Officers (not called Junior..) and Captains.
I don't see something wrong with that.