Agree 100% about the Ambience. I guess Jolla's reasoning is that eg. when you go into a meeting, you might want to stick a silent Ambience on, so a quick change is essential. I think it's overkill. As other's have said, one of the directions would be better suited to the last open app.

The Ambience selector is also present on the Task switcher screen swipe, where maybe a better use could be found.