Thanks for flagging us here. The current “Play All” behavior is based on the same algorithm that Radio uses for making selections, the difference being that Radio selects from an algorithmically generated set of similar content, whereas Play All is playing from an explicit group of content you’ve selected (ie, the Focus, your whole library, etc). Play All shouldn’t get stuck on the same artists and tracks over and over, and we’re going to address this when this area of the product gets overhauled.
As I mentioned in the post linked above, we are planning to devote proper attention to the Radio feature, and for now we’re avoiding making changes here piecemeal, or implementing quick fixes. This feature deserves first class attention, and it will get it. I don’t have firm timelines on when that’s going to happen, but we have seen all the recent questions about random playback, and we’re aware that this is a important use case for a lot of people.
What we hear from you guys really does drive how development resources are allocated, so thanks in advance for the feedback, and please keep it coming all.
One more thing:
One thing you might want to look into is our recently-redesigned Tags feature. An easy way to think about Tags is that it’s like a playlist, but with two major departures: 1) it has no order, so playing a tag is always shuffled; and 2) tags can include way more than just Tracks, including Artists, Genres, Composers, etc.
If you tag 10 artists, you can just play the tag and it will include albums by those artists, tracks they’ve appeared on, etc. Same with genres, etc. One thing you can’t do is selectively remove content from the tag. So, if you have 10 Miles Davis albums, and want them all included, you can just tag Miles. If you want all but one album, tag all the albums. If you want all but one song, go to Miles’ page, View All Tracks, and tag all but one.
It’s not yet possible to tag a Focus, but we are hoping to include that in the future, to provide “smart playlist” like functionality.