[DaveNP]

The only auto I've owned was an 850 between a manual 850 and the present manual V70, so observations from then-
It was quite easy to get up to and over the 30mph limit, press the 'go' pedal and off it went.
With engine noise and revs, it always seemed to rev more than I would do in a manual but it was limited not to over-rev into the red line, I possibly don't rev the manual enough as the optimum power doesn't come in until the revs go up.
I found in Drive on level ground it would start to move forward without any throttle if the brakes were not on and it would hold itself on gentle slopes. You should get used to it with time but if you're in doubt, you can brake with the left foot while giving it a little throttle to ensure it does move off on a steeper hill.
Drive or Neutral at the lights? That's a bit like with a manual box, do you sit at the lights with your foot on the brakes and clutch? In theory no but a lot of us do it, in either case the damage and wear will be over the long term.
The lack of engine braking can be an issue if you're used to using the gears to slow down, my father never really managed to get used to that.