iPhone Duo Makes Focus Modes Easier to Toggle From the Lock Screen

When a Focus mode is active, a new button appears above the bottom controls that lets you toggle it off and on while you remain on the Lock Screen.

The problem is when there's no focus mode active, you can't long press there to activate one, so you have to dive into the control centre, hence the workaround I talked about above.

Can we also replace the lock screen controls to others from the camera and torch like other iPhones? Since they introduced the camera button I find the lock screen control redundant

This is already exactly how it works on current devices. When a focus mode is enabled then there's a line of text and an icon in the space between your two buttons in the corners. You can long-press on this already to change the focus mode.

This icon on the side is probably just where it goes instead on the duo.