It's one thing to say it works well for you.
It's quite another to malign folks who disagree with you.
For instance, I never liked or used cover flow. (I don't like it in Safari history, either.) But i would never suggest that the folks here who loved it or found it useful are whiners, or making something out of nothing. To them, it was important, and to attack them personally for seeing this little part of the world differently than you do seems kinda mean and unnecessary...
Me, I CONSTANTLY had multiple playlists open in addition to the main itunes screen. I resized windows and set them up like tiles so I always knew what window was where and could generally click on whatever one I needed. And if a playlist window was buried, the "windows" menu became a bookmark list. With multiple windows I could play one playlist while searching or updating another. I could compare lists, and therefore evaluate smartlist search rules. I could highlight a song that i was tagging in one list, go to another list (or several others), and still have that song highlighted when I came back to it...even if it was days later.
Now from what i can tell from reading through these threads, very few people used the ability to have multiple playlists open. But there were a few of us-- (mostly large-library anal power users, from what i've read--my itunes library is a few gigs shy of filling an external terabyte drive. The fact that I know I will never ever finish adding artwork, and properly tagging genres and smart list keywords (in the groups field) in no way eliminates my desire to try.) --and there's no reason to suggest that there's something wrong with us because you (or for that matter, "most users") didn't use the features and functions of itunes up through 10.7 the same way we did. And you ought not be so dismissive of folks not like you...
And besides all that... I just think Apple has always been a computer that folks can spread out with and use in their own way... Multiple applications and windows are at the heart of that, and turning itunes into a one size fits all, only one way to play, goes against what Apple has always meant to me... YMMV... But if it does, Bop, I'm not so sure i want you to tell me... ("If you can't say somethin' nice...")