Also, it's nitpicking, but I wouldn't argue that Windows Explorer has the most usable interface. Usability is highly dependent on the user. Some benefit from an even simpler looking UI like the Nautilus UI in more recent versions of Ubuntu while others can figure things out easily on their own and benefit more from having lots of features at perhaps the expense of a clean, simple UI.
a powerful feature set doesn't have to look like a mess.
Windows Explorer is a reasonable example(and one everybody will know) of this, it achieves a relatively robust feature set and cosmetic set(for different style data/people), while not looking like something as ridiculous as
this.
all i was saying, is that given a choice of two extremes between designed to look like a movie, and Windows Explorer, i'll take the functionality.
for a game ideally the goal is something that isn't a mess and has a wide feature set, while still looking as a part of the game. absolutely.