I've recently been looking for more classic top-down style shooter games (Alien breed, Close combat, etc.), but this is proven much more difficult than I had hoped. My search has brought me to the realization that there's one aspect of games that has always been lumped in with genres, even though it isn't exclusive to any of them; the player perspective.
I now think that including the player perspective in the definition of a genre makes the entire system more complex and much less flexible. For example, a "first-person shooter" is consider a genre, but there are first-person games out there with little to no shooting in them (Portal, Gone Home, Mirror's Edge, etc.). Now we could create a genre definition for each type of first-person game like; first-person adventure, first-person puzzler, etc., but this would be a bit redundant.
However, if we take a look at the examples above we'll notice something in common; player perspective. Would it not make more since to separate the concept of perspective from the concept of genre? We already have genres for adventure, puzzle, platformer, etc., but anyone of these styles could use a different kind of perspective. Since the player perspective is an idea shared between all games it seems quite logical to place it in it's own category. Now alternatively we could defined each kind of perspective as a genre ( third-person, Top-down, etc.), but I think we can all agree that a perspective by itself is just that, and not a genre.
So would placing perspective in it's own category not make sense? I'm very interested to hear what other people might think of this idea. My only goal here is to make it easier to define and filter games. With a system like this in place I could easily find top-down shooters by filtering the results by perspective “top-down” and genre “shooter” while searching the wiki. As the system exist now I can only choose between shooter, shoot 'em up, or dual-joystick shooter. Which would return results far too broad or narrow for my liking.