The last time Google made new alarm, notification, and ringtone sounds for Android was for the original Pixel and Pixel XL. Maybe this will become a yearly tradition, because Google has done the same thing for this year's Pixels. We've also extracted them from a Pixel 2 XL, so you can use them on your own device.
All of the previous sounds have been replaced, so if you still want the old ones, you'll have to download them from the above link. I think 'Icicles' is my favorite alarm out of the bunch:
My favorite notification sound is probably 'Duet':
And finally, I think the best ringtone by far is 'The Big Adventure.' It sounds like the opening theme to a animated show:
On a similar note, the menu for selecting sounds has been revamped on the Pixel 2. It's not a pop-up anymore, instead filling the entire screen. Here's what the same menus look like on the original Pixel with Android 8.0 Oreo:
If you want to try these out, we've done the hard work for you and extracted them from a Pixel 2 XL. You can download them below. Just place the files in the Alarms, Notifications, and/or Ringtones folders in your phone's storage (/sdcard/) to see them in the sound picker.