Editable Element Styles without remove (better UX for us)

Element Styles should be editable in Appearance panel without the need to be removed

I understand what you mean, but the goal of a style is to be applied without modification from anywhere. If you remove it from dropdown, it mean that the element have it own style. Maybe you should say: See the style setting in the appareance style and if modified, remove it from dropdown of style applied? (And better, automatically select a style if the settings are the same of an existing one )