iCloud How to remove music and photos safely all at once?

[patent10021]

My current phone is 256GB and about 130GB is being backed up by Photos, social apps, Music, iMovie, and Notes etc. This is a mistake and inefficient since I am paying for iCloud 2TB and am currently using only a fraction of that 2TB. 100GB is from Photos and I really do not need that. When I buy a new phone I'll be choosing a 128GB model since I have iCloud 2TB.

1. I want to remove the music from my iPhone [all at the same time] without deleting the albums from my library.
Maybe I should just delete the Music app, reinstall it and grab again from iCloud as needed? But then I won't remember all the albums that were on my phone. Tough luck?

2. I want to remove all my photos but ensure they are on iCloud first.
Just make sure iCloud Photos is enabled in settings? But then only 30 days is visible right? If I want to view older photos I have to go to iCloud.com and look at them?

Advice/caveats?

EDIT: Ah, first you need to turn off "iCloud Photos" then you can delete photos from iPhone while still keeping them in iCloud. Pretty dangerous if you miss that step. But then when you turn "iCloud Photos" back on after you've deleted photos from your phone, you will only see the last 30 days from iCloud right?

 

[patent10021]

For Music I found the easiest way to keep the albums in the library but remove the music from the phone.
Settings-> Music -> Downloaded Music and just remove from there. Only the music is removed while keeping the albums in the library.

Music app should have an option to remove all music from phone all in one shot. You can remove all of them from the area I just mentioned but the app UI itself doesn't have that option. Seems pretty obvious to me.

p.s. How is Notes app storing 5GB on my phone when it's an iCloud app? How can I keep 100% of the Notes app data in the cloud?