>>47454327Traditionally, Normal-types meant "less remarkable" or "aboriginal". (Like the word 'normal' means, duh.) A lot of Normal types in Gens 1 and 2 have very direct and literal links to their real-life animal counterparts.
The rat that looks much like a rat - Rattata - is Normal type in a similar way that Tauros, a literal bull, is also Normal type. I say the closer they look like to their origins, the more "Normal" they become.
Now, starting with Girafarig, we have a new breed of Normals where there's something significant, yet still unremarkable about them. (i.e. dual-typed Normals) Take Sawsbuck, for example. It is very much defined by its Grass-themed antlers, yet it still has a large and obvious resemblance to a buck. (The brown fur, for example.) Diggersby is another example - It has a dirt belt, but not much else separates it from the deformed rabbit that it's based on. The gray fur and puffy ears resemble a rabbit directly, dictating its Normal type.
I think the most unorthodox use of the Normal type so far is with Drampa, the Dragon/Normal type. Its unique design definitely doesn't match the above description of Normal types, and yet there's still something about it that makes it seem Normal. My opinion is that his friendly design (and nature) makes him less of a true dragon, since most dragons' designs are very menacing. (Garchomp, Druddigon, Hydreigon, etc.) It's more about him being less of a Dragon, rather than more of a Normal. Normal, as you can tell, is probably the most flexible type in the game, so there's bound to many new and interesting uses for it.