It's probably been covered, but I leave the Whispernet off (unless I'm buying books) and just leave the Kindle on all the time. I hit the alt and A
A keys to put it to sleep rather than turning it off.
However, I also keep the charger by my bed, and usually leave the Kindle charging overnight.
I got used to the buttons fairly easily. Most often, I read with the Kindle in the case, both pages open, and my left thumb up turning the pages. I have long fingers ... so that works for me.
Most of the time, I do my shopping on the computer. It's nice to have the ability to buy books on the fly, and I have done that, but it's not my method of choice.
I created a bookplate screensaver with my name, address and phone number on it just in case. Unlikely that I'll lose it ... but you never know.
I hope you enjoy your Kindle.