Thanks.
Hmm... The stats in the DMG do not actually reflect the fact that the kama-part is always held in hand for the close combat and the ball-on-chain is the reach-portion.
How about these:
I buffed the weapons very slightly, to balance the 'damage self' portion.
{table=head]Kusari-gama|small|medium|critical|damage type|special
Blade|1d4|1d6|×2|slashing| Light weapon
Ball|1d4|1d8|×2|bludgeoning| reach, trip[/table]
15 gp
When using a Kusari-gama, one gets a +2 bonus on opposed attack rolls made to disarm an opponent (including the roll to avoid being disarmed if such an attempt fails).
A proficient user can use the Weapon Finesse feat to apply one's Dexterity modifier instead of one's Strength modifier to attack rolls with a the ball-and-chain portion, even though it isn’t a light weapon.
Rolling a natural 1 when attacking with the ball-and-chain portion leads to the user damaging oneself.
Goblinoids treat a kusari-gama as a monk weapon. Hobgoblin monks are proficient with it.
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{table=head]Meteor hammer|small|medium|critical|damage type|special
Ball|1d8|1d10|×2|bludgeoning| reach, see text[/table]
25 gp
A Meteor hammer has reach, so one can strike opponents 10 feet away with it. In addition, unlike most other weapons with reach, it can be used against an adjacent foe.
One can make trip attacks with the chain. If One is tripped during one's own trip attempt, one can drop the meteor hammer to avoid being tripped.
When using a meteor hammer, one gets a +2 bonus on opposed attack rolls made to disarm an opponent (including the roll to avoid being disarmed if such an attempt fails).
A proficient user can use the Weapon Finesse feat to apply one's Dexterity modifier instead of one's Strength modifier to attack rolls with a meteor hammer sized for one, even though it isn’t a light weapon.
Goblinoids treat meteor hammers as monk weapons. Goblinoid monks are proficient with them.
A natural 1 on the attack roll leads to the user damaging oneself.
Note: Maybe I should lower the damage when used in close range, and make it act as essentially a dire flail?
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Snagger's meteor hammer (Interested in seeing a better name)
{table=head]Meteor hammer|small|medium|critical|damage type|special
Hard Ball|1d8|1d10|×2|bludgeoning| reach, see text
Soft Ball|1d8|1d10|×2|Subdual| reach, see text[/table]
A special version of the meteor hammer, the snagger's hammer has both a hardened head similar to those of normal meteor hammers and a padded head. While equal in weight, the padded head is special in that it deals nonlethal damage, allowing the wielder to choose if the target is to be subdued or slain. It is otherwise identical to the meteor hammer described above. The snagger's meteor hammer shares proficiency with the standard meteor hammer - knowing how to use the latter is enough to be proficient with the former.
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Rope dart:
Slashing or piercing weapon with low damage but reach 15, otherwise similar to the spiked chain, perhaps?
I will probably remove shuriken, siangham crossbow and maybe the javelin from the monk weapons' list for goblinoid-designed martial arts to keep things more even though.
Alternatively: Goblinoid monks who learn a variant fighting style tend to choose Cobra Strike or Sleeping Tiger combat styles. However, only Bhukas have ever learned Passive Way or Hand and Foot - no goblin or hobgoblin has ever mastered either to a sufficient level to teach others and thus, non-bhuka goblinoids cannot learn either unless presented with extraordinary circumstances.