That app-note is great, amazingly detailed.
I'll try and measure a bit, what I'm not sure about regardless of mode, deep-sleep/hibernate, is when say having all GPIO's set to inputs, wake on falling-edge (i.e. button shorts to gnd when pressed with internal pull-up on the gpio)
just one gpio doing the same. Would that make a difference in the overall power consumption.
I see in most app-notes they state wake-irq on rising-edge. Also doable if changing the button scheme from common gnd to all being pulled together say 1.8V and have all gpio's have a pull-down instead. Pros/cons?
I think even defining interrupt on both edges for an input pin will not have much influence on power consumption, but you may try out.
I would always recommend to use pullups, so you do not have power at the (external, accessible, vulnerable) switches.