Change is Good...but beware the feedback
If you want rile some users just change the interface.
Linux with its many flavours of interface supposedly has this covered but even then these interfaces are changed for the better/worse. and if your favourite flavour of Linux decides to switch allegiences it is bound to start a riot.
Windows fell down this rabbit hole with Vista and again with Windows 8 and continues to this day with subtle changes and general moving of stuff around in Windows 10.
Constant tinkering with the user interface will lead to user disatisfaction. ser want all the nice new whizzy stuff but woe be tide anyone who actually changes something.