As far as I remember click "?" mark on the bottom of map window - there is option to change it back to map classics. You can save this as well once changed (small pop up will come out) so it will become your default.

For Google Maps you can click on the help button on the bottom right and choose "Return to Classic Google Maps".

The new Maps has come a long way since launch but I agree that it's still very far from good.

Yep, I still find myself switching to the old version so I can get terrain view. In the new version, once you type in an address the "terrain" link below the address box disappears. I can't imagine why that is supposed to be helpful. My typical use case is that I click a map link for a hike, enter my address to see how long the drive is, and then want to switch to terrain view to see terrain for the hike. Apparently, that is no longer possible.

Agreed, I think GMaps is probably the best example of "we have too many people working on this and we need to give them something to do". Perhaps people could have accused me of just needing to "get used to it" a year ago, but after a year of usage I find the new GMaps less useful in almost every way.