Everybody appears to have an idea of what the bodywraps of mighty strikes should have been. Here I present my take on it. The advantage: can be used for unarmed-only as well as unarmed+weapon monks (provided the unarmed-only monk doesn't mind having his walking stick (ki resonating quarterstaff) to hand). Additionally it can help a little to get around DR and can potentially escalate to +8 equivalent weapons.
Price +2 bonus
Aura moderate transmutation CL 12th
A ki resonating weapon, when held or wielded, grants its enhancement bonus to the wielder's unarmed strikes. A wielder with a ki pool may spend 1 ki point to grant all melee special abilities of the weapon to the wielder's unarmed strikes for one round. When doing so, the wielder's unarmed strikes bypass damage reduction as the weapon would in addition to the damage reduction that the unarmed strikes bypass inherently.
Construction requirements
Cost +2 bonus
Craft Magic Arms and Armor, creator must be a monk
Comparing with Amulet of Mighty Fists
Amulet of Mighty Fists +1 5000gp
Amulet of Mighty Fists +2 20000gp
Amulet of Mighty Fists +3 45000gp
Amulet of Mighty Fists +4 80000gp
Amulet of Mighty Fists +5 125000gp
+1 ki resonating weapon 18000gp (+weapon cost)
+2 ki resonating weapon 32000gp (+weapon cost)
+3 ki resonating weapon 50000gp (+weapon cost)
+4 ki resonating weapon 72000gp (+weapon cost)
+5 ki resonating weapon 98000gp (+weapon cost)
+6 ki resonating weapon 128000gp (+weapon cost)
+7 ki resonating weapon 162000gp (+weapon cost)
+8 ki resonating weapon 200000gp (+weapon cost)
As the list indicates, a ki resonating weapon costs about the same as an amulet of mighty fists at the +3 and +4 range; before that the amulet is significantly cheaper - and at +5 the ki resonating weapon is noticeably cheaper. At the ranges +6 to +8 it would appear to be a steal for a ki resonating weapon - but keep in mind that weapons are limited to a +5 enhancement bonus; meaning at best the weapon would grant a +5 enhancement bonus to unarmed strikes all the time; while the special properties (such as flaming, wounding, keen) are only granted to the wielder for a round when he spends a ki point.
As a concept, I really can't say I'm keen. The monk needs better options, but I think the monk itself needs fixing, not the items. The idea that to be effective in unarmed combat I have to be holding a weapon is...well...counter-intuitive to say the least. If you have to hold a weapon to fight unarmed effectively, your defeating the point of fighting unarmed.
I'd like the concept a lot more if the monk could use the ki-resonating property to apply their unarmed damage instead of the weapon's base damage. It may not make a lot of difference, but it feels a lot less silly.
I was thinking that its not very intrusive for the monk to wield some benign knuckles or have some other unobtrusive weapon, or hold a quarterstaff. Additionally, I think this concept goes the distance for any monk that wants to weapon+unarmed; as currently that involves buying a 2000 weapon and a 5000 amulet.
The more important thing is the balance of cost vs result.
Problem is most monks go weapon or unarmed. The only regular exception I can think of is the zen archer, who would use unarmed strikes when enemies close with them rather than their bows, but then the unarmed strike is a secondary weapon. Otherwise the monk will want either a good weapon with good enhancement (wasting +2 is not an option until later levels) or else they go unarmed and get an AoMF as soon as they can.
The other problem is that the level at which the monk most struggles with lack of enhancement is at low levels (3rd is when it starts to bite), and this doesn't help there.
Problem is most monks go weapon or unarmed. The only regular exception I can think of is the zen archer, who would use unarmed strikes when enemies close with them rather than their bows, but then the unarmed strike is a secondary weapon. Otherwise the monk will want either a good weapon with good enhancement (wasting +2 is not an option until later levels) or else they go unarmed and get an AoMF as soon as they can.
Given the current ruling for flurry - you cannot use a single weapon, you have to go with two weapons.
Problem is most monks go weapon or unarmed. The only regular exception I can think of is the zen archer, who would use unarmed strikes when enemies close with them rather than their bows, but then the unarmed strike is a secondary weapon. Otherwise the monk will want either a good weapon with good enhancement (wasting +2 is not an option until later levels) or else they go unarmed and get an AoMF as soon as they can.Given the current ruling for flurry - you cannot use a single weapon, you have to go with two weapons.
The current ruling that was revoked pending the full look the monk needs anyway? Basically that ended up with "Er, use whatever it was you were doing before, we'll get back to you" which means it could go single weapon flurry or it could go TWF.
Besides, Sohei and Zen Archers are nerfed if it's TWF, but not if it's single weapon flurry. They can still make unarmed strikes, though. So if you wanted an armed monk you would go sohei or zen archer, and if you wanted an unarmed monk one of the other archetypes or core monk.
Also, how many warriors that go TWF use two different weapons, other than sword & board (which is done because of the shield bonus to AC as an added benefit)? You use two weapons the same because of the feat economy for things like Weapon Focus.
The point remains, you tend to go one or the other. A TWF flurry just means more will go unarmed completely.
I mean that you need to enhance two weapons (even if they are both temple swords). Mathematically the ki resonating property offers good value for money in such a setup both for unarmed-only and unarmed+weapon fighting (both would only cost the enhancement of a single item).
Except that if I want two weapons, enhancing both costs about the value of an extra +1 on a single item, and this effect costs the same as an extra +2. Even with ki-focus, the cost is about the same.
I can see where it would work, but I think it's niche, it's not thematically very good for an unarmed fighter to need a weapon, and it doesn't fix the monk's other problems by any stretch.
You're math is based on a faulty assumption: by looking at the two +2 (2x8000 = 16000) vs one +3 (18000) case you assume that it generally applies in all cases.
Compare for example: two +7 (2x98000 = 196000) vs one +8 (128000).
As I explained in the opening post, the +2 bonus is about on-par at the +3 and +4 case; then afterwards is actually cheaper than upgrading two weapons separately. Quite a bit cheaper actually.