And you already provided a list of candidates. I love it.
It would help to divide the list into sections: uniforms, field equipment etc.
Thus everyone who has something to contribute could easier see what's there and what could still be added.
The first item that comes to my mind is the leather Starfleet Tunic Wrap worn by Charlie Evans in "Charlie X".
With the new additions of TOS-R it might be a simple solution to add a TOS-R section. Thus people who can't find something in the TOS section would look up the TOS-R section (and understand it's a new addition and/or alteration of TOS).
I will come back soon, but currently devote my time to the saucer's deck plans as I've fallen behind schedule.