You know what? I like this.

I'd implement it.

Dual wield claws. Spears are good for offense and defense, so it's actually a weapon I would use heavily with that build.

Not sure if it gives perks to weapontrip, that would make it nice to use for any race if it does though.

Besides that, I think spears on thieves could use a bonus.

Maybe your thief is less a thief and more just the roguish type like Matrim Cauthon from Wheel of Time. Or like Gambit. You use the spear for RP purposes. Sure nice to have a bonus, but I do like the things that exist which aren't necessarily ever a great option but fill RP niches.

For some reason I never stick with a thief beyond like level 12. I did have a role once where my thief was a janitor. Cleaning up outside the thieves guild, some rich dude walks by, mr. janitor man thinks to himself "why not me?," then tosses his broom to a disgruntled cityguard and waltzes in.

Something silly like that. He uses spears because he is so good with a broom!

Why do I write this nonsense...

You don't need a weapon skill to wield the weapon.
So for Rp purposes you can wield anything.

I always wanted to play an arial that used the rotting dentures exotic for example, because damn it, he's always wanted to know what it was like to actually chew his food!

Or he's old, all his teeth are gone, so this old human warrior (hpm) dual wields dentures so he can eat you after he kills you.

Stupid things like that are fun, even if not PK viable.

One of the hardest things to do in CF:
Roll a character with the sole intention of being a PK Victim (you have to give people a challenge enough to entertain them, but you have to lose 90%) that still has fun for both you and people who fight you.