I understand your aesthetically question who take care of the history of user interface design: many DE you’ll find on Linux are inspired by Windows and Mac OSs, and so typically Gnome is more near to mac while KDE to windows; keep in mind both are completely customizable. There are also other original Linux interfaces who brings something more exotic (old Ubuntu Unity or window managers like i3-wm) but most of these are used by few since UI’s comfort tend to unify everything.