It is obvious that F/O will have an improved sense of a successful flight as PF if he can be given maximum responsibility. Except for low time F/Os, a major difference between Capt & F/O is confidence. There are enough confidence erroders out there without reducing some of their PF opportunity.
Aviation safety is affected by cockpit morale. In a 5 sector day, my F/Os were almost always PF for at least 3. I think many of them will perpetuate this principle rather that the more common practice of alternate legs commencing with Capt. The lifting of confidence and crew management skills was very gratifying to observe.
Crew is a complete package. Capt and operator should encourage maximum reasonable responsibility, including taxi where possible, for our captains-in-waiting.