Well, I spent 45 minutes on the phone with Apple support today. They documented the issue and had me send them screenshots from my iPhone. The senior advisor I spoke with even checked his own phone and confirmed that his music library seemed to be randomly divided into artists with "simple album lists" vs. "not".
...And then, after I got off the phone I started looking through my music library (iOS) more carefully, and the explanation somehow jumped out at me:
The dual formats were in fact not random, but based on the _number_ of albums of a particular artist in my iTunes library. I dug around a bit until I discovered the precise dividing point:
Artists with 4 or more albums in my music library (doesn't necessarily have to be complete albums; could even be one song) are afforded a sub-menu list of their albums (i.e. a simple album list).
Artists with only 1, 2 or 3 albums are not given this clean sub-menu of albums. (Instead, as described in my original post, their music is listed in one continuous "ladder" of songs, grouped by album.)
My guess is that some iTunes (iOS) designer thought it wouldn't be too burdensome to scroll through a couple of albums worth of songs to get to a third album in a short list. And, maybe they also thought the screen looked too bare with only a couple of albums listed, so they figured 'why not fill it up with songs?'
Here are two reasons why I don't support this design decision:
1. Menu consistency. All artists' content should be formatted the same. I'd like to see a simple list of albums for ANY artist, regardless of how many of their albums are in my library.
2. It can still be burdensome. Some albums (e.g. box sets) contain dozens, or even a hundred or so tracks. Having to scroll through that long a list in order to get to a second or third album shouldn't be necessary.
