I don't find it any easier to back from one side or the other. It is much more important where the obstacles are, both behind you, and in front where the truck has to swing. Just practice whichever way your driveway requires.
As for traffic, I live on a fairly busy street. I wait for traffic to clear enough to get my backup started. After that, screw'em, they just have to wait. And I'm not going to pay them any attention. That needs to be on my rig. In truth, once in a while someone will honk, but mostly people are engrossed in watching me do something that they don't have the nerve to attempt.