Thanks for the quick, detailed, and helpful response!
I was being pessimistic about the power requirement based on my last pi project which I ended up having to buy a powered USB hub and moving peripherals to it. But that was with a camera and two wifi dongles plus the occasional USB keyboard. So, as you suggest, I should just measure the actual amperage of the device with the single wifi dongle I’ll be using.
I have two servos because I’m using the engraver attachment. I know it’s not really a servo, but I was making the (possibly poor) assumption that it had similar characteristics because it plugs into a servo port and is driven from the same rail. I’m not planning to drive the servos from anything other than the EBB, I was just figuring the highest total load on that voltage regulator would be whatever the PI pulls plus the peak current from the engraver motor and pen lifting servo.
I guess I should measure the eggbot too and then just add together the two numbers I get.