Back into every spot every time. That is something my wife has heard me say a billion times, and I've said it to many people. Back in to parking spots, it is always safer and easier to pull out forward. Backing in, you're already in the travelway, you and others are aware of one another's existence. I also think it's easier to maneuver into a space when your pivot enters last. Also helps you practice backing up, for situations where you may need it.

Granted, all of this came from driving ambulances, where the lesson was, no matter how steep and windy the driveway, backing in it with an empty box is always easier than backing out with a patient in the back.

I will concede there are exceptions, anyone can feel free to list them.

Furthermore, I've seen some municipalities institute back in angled spaces on roadways, and they are absolutely the best. Anytime a road has non-parallel parking spaces, they should be back-in spaces.