iirc the only weapons which allow you to use your Flurry of Blows ability are a Kama & "unarmed" (gloves)
Kama's free up your bracers/gloves slot for other equipment if you feel the need, and will do d4 with 20/x2 crit chance. They can also be easily enhanced with magic spells like Greater Magic Weapon, Keen Edge and Dark fire/Flame Weapon. At early levels a Kama may not do as much damage without enchantment as your unarmed attacks, but while supported by a mage they *may* average more damage, or have interesting effects "on-hit". Kama's are also much more common than other monk weapons, and come in greater variety.
Unarmed attacks will scale with your character starting at a d6 (d4 if your small) eventually getting up to a d20 (d12? if your small). Unarmed attacks benefit from your Ki-Strike ability you will eventually gain. Gloves can enhance your unarmed attacks by adding unique effects, or elemental damage. Gloves (especially powerful ones) are much less common but for raw damage output later in your monk carer are a good investment.
Avlis Wiki also lists a few other "monk weapons" in which they have proficency, and depending on your monk level you will retain your "monk attacks". Monks progress on two different attack scales the "normal" +15/10/5 and specialized monk weapons which provides 2 more attacks. While these other weapons can't gain the additional attacks from Flurry of Blows, if your high enough level you will keep your enhanced attack bonus for using a monk weapon. Quarterstaves, Nunchaku, Kusari-gama, Tonfa, Wind Fire Wheel etc. are all unique weapons some of which have properties your very unlikely to get on a Kama or pair of Gloves.
At the end of the day the choice is yours. But in specific answer the general philosophy is Kama (early levels), Gloves (late levels).
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