Why are there trade limitations?

Ah, I see! Except, not so much for diversity reasons because most of  the characters I see with trades are either Mercenaries or Hunters or Scouts. I don't think it would necessarily make someone feel less important being in a multitude of Hunters or the like either, because (realistically) all wolves should be able to hunt, fight, instinctively predict weather anyway. It's more of a matter of if you (the player) wants to spend time advancing the personal (specialty) affects of your character.

 I, personally, wouldn't seek them all either. But there are at least three categories into which I can fit Diane, and I was just frustrating myself trying to do eeny-meeny-miney-moe and not feeling satisfied with what I landed on lol

As for impossibility, I think we all know our own characters and should be able to accurately gauge what they would and wouldn't be good at. Like, I don't see Farstep being a Counselor, but he could definitely be a Novice Caregiver by pupsitting or the like. Except, he wouldn't be able to pursue this trade (even if you did threads relating to pupsitting) since he's already a Guardian and Scout, you see.

I just think you should be able to earn trades through IC demonstration and not be limited to what you can actually achieve in that manner.