Title pretty much says it all.
Two Weapon Fighting definitely allows Unarmed Strikes as it specifies that Unarmed Strikes count as Light Weapons.
I can't seem to find anything in the rules that prohibits Unarmed Strikes from benefiting from the Archetype abilities that the Two-Weapon Warrior gets.
I understand that the names of the abilities don't lend themselves to the idea of Unarmed Strikes, but then they don't always work with actual fighter weapons like Quarterstaves, either.