[Android][Root] Why I need the root?

1. In older devices I need the root for change default DPI, because I like small fonts and icons and a lot of space. - Now in new versions of Android we've go it inisde System settings and Developer Options.
2. Last time I need root for change default settings in chrome - turn off "Mobile Mode" and I would like to switch to "Desktop Mode"
3. Some paths are locked for user - in example: ../../wpa_supplicant.conf to read the password of Wireless Networks - I need root to read this file in My Own App to remind password on saved network.
4. New Android versions have two kinds of connection with computer:
• MTP
• PTP
• But it works fine with Windows OS and worse with Linux OS, even if You have installed *mtp* package in your Linux.
  I want to connect it as normal USB Flash Drive
5.  ...to Be continued