chrefrp:
I don't think it would make sense to put a flight engineer in the cockpit. The systems in question have extremely limited inputs. In reality they should be simpler to troubleshoot than even the most simplistic systems one can think of. Additionally most of the real troubleshooting can only take place on the ground anyway.
Situation awareness is something that may need some additional work when looking at self-healing systems (this isn't really an FBW issue) but that is a separate issue.