Worth noting that the EDPs will provide some useful pressure right down to approach speed so you are using the yellow as a top up.
Having yellow hyd gives a lot of advantages, configuration is one but braking/steering is also useful (newer A/C use yellow for nose wheel steering).
On the elec configuration subject. After a dual eng fail or Emergency Elec Config, even if you recover 1 or 2 main generators the essential buses remain supplied by the emergency generator until reset on the ground although other services are recovered through main buses.