It was the first thing I changed after getting my mac. I have not needed to login to my admin account besides the first time I set it up. When I need to do something that requires the privileges, it just asks for the user/pass.
That's exactly what an admin account does. Are you sure you know what the hell you're talking about?
iTunes is touted as a music management program. Most of us have a well structured Music folder.
Then don't click "Keep iTunes Music folder organized". You can organize your music folder however you want.
What if you buy DRM free MP3 music online ? Or free music available from indie bands ? You should be adding them manually to the iTunes library ? I don't think so.
After you get the music, drag it to iTunes. It takes literally one second. I don't understand what the problem is.