Can you put some numbers to that reasoning?

For example just how much current will flow from these 3U battery packs on a continuous basis, and how much current do you think is needed for 9 servos?

Keep in mind that the only ones that will ever be at full deflection for more than a few seconds are rudder and occasionally ailerons.

The surfaces on this plane are not so huge that you will ever stall the aileron or elevator servos, so the only real problem is the rudder. Use 2 5955s there and it will be unlikely to stall too.

I just wonder if you are worrying about a problem that you won't have.

TF