Here's an explanation of my typical behavior when using Spotify, to try and help explain why I consider these points a major problem:
Quite often, when I launch Spotify, it is to find something new to listen to. To achieve that, I use a number of means, one of which is the absolutely fantastic "Discover" functionality (I love it!). Typically, I listen to some recommended artists/tracks/albums, and when I find an album or artist I like, I click "Play" on top of the track list in the album view and start listening.
Then I continue browsing and discovering and, when I come across something else that I find interesting, I can no longer choose to "play" it because it would completely override the current play queue, the currently playing track included, and start playing the new album I just found. So the only option is to "queue" it.
Now, this is where the problems kick in. Instead of being queued up nicely at the end of the play queue like it should do in my view, this new album is like the neighborhood bully, cutting in line straight to the entrance. If I leave things the way they now are, I'm going to hear the currently playing track... and then the entire new album I just "queued" up... and only after that do I get to hear the rest of the tracks I first chose to "play".
If, at this point, I keep on browsing and discovering and finding more interesting music, I can pretty much only keep on "queueing" them up which means that the rest of the first album just keeps getting pushed back further and further. However, the neighborhood bullies seem to respect one another, so all music added beyond the first "queued" tracks take their place at the end of the queue, like they should.
Sure, I could just "queue" up the first album as well but I really dislike the way the whole "queue" functionality has been implemented - simply because I want to be in full control of my play queue which means that I want to be able to move any track to any position in the play queue regardless of how it was added there and I want to be able to delete any track I choose from the play queue at any time.
Also, I would very much like to be able to just add like a 100 tracks in the play queue, one track or one album at a time and then hit "Shuffle" to have them play in a random order. With a vast majority of the tracks being "queued" up this does not happen.
I hope this helps at least some people see things from my perspective.