I wouldn't conflate "best" with "most important". Personally I find the sappy emotions like love, happiness, and contentedness to be the best ones, generated by the best parts of life. However, I would absolutely say it is the most important feeling from a self-preservation standpoint.

There is also something to be said about today's unchecked, underutilized anxiety that one feels when sitting doing absolutely nothing. There has been an unending discussion about the causes of this, but I tend to align with the belief that since our current world doesn't provide many dangers for us to genuinely cause anxiety, our brain freaks out and finds less dire avenues to trigger it.