So, I have been skimming over the armor, trying to figure out which armor would act like a quilted jacket.  Easy answer is "duh, leather," my passionate hatred for the concept notwithstanding.  The problem is that there are …issues with Leather armor.

First, leather armor is poorly defined. The discriptions generally called it "flexible," making it resemble buff leather however the armor is broken into 5 individual units similar to plate armor: A cuirass, pauldrons, vambraces, gorget and leggings. The fact the armor has to be broken down into components suggest that the pieces are actually quite stiff. The last issue is the absence of lower leg protection, ie: greaves. In all other cases of armor, there is a corresponding boot, but there are no "Leather Boots." Well there is the "Boot" but that is supposed to be clothing, not thick enough to act as armor.

So, my suggestion is to figure what "leather armor" is, without relying on game bias. Here are my best options:
A) Remove leather from the armor shop outright. The problem with leather is that, in order for leather to function as armor, it has to be extremely thick. Biker vests, fetishwear and comfortable leather boots simple cannot be thick enough to act like armor. It would, however, be viable as a substitute for other clothing
B) Combine all the components into a single item. Using the 17th Century buff coat for inspiration, all 5 parts of a leather harness could be replaced by a single piece of armor that would behave sort of like a Hauberk. It would prove somewhat cut resistant and could be clearly worn under other heavier types of armor. It could also sub for a gambeson (though I'd prefer it be the other way around).
C) Define leather as "Heavy Armor" and add a pair of greaves to the shop. Combining elements of Japanese Lamellar and cuir bouilli, leather armor would retain much of its current nature. There would, of course, be some modification of definitions, since "hardened leather" is quite…well hard, but it wouldn't force people to change their inventory.

As an aside and possibly related note, I also suggest removing the Gorget. As it is, it simply appears to be a redundant collar for what is currently no more than a leather vest

"without relying on game bias."

But… this IS a game, so these bias exist.  The armour in the shops is vague for a reason; to allow players to have some more freedom in how they use that armour, within the limits set in the items description.  So, while you might be talking of actual leather, my character, Larka, wears elven made leather, which in a high fantasy game such as this, is generally thought of as more flexible and more protective, because elves know how to make really good leather :P

This isn't a real life Earth place, the world itself is called Revaliir, I mean we have dragons and succubus and stuff running around :P  I'm sorry, but you so closely compare the real world applications to leather(in this case), to what is used in most fantasy games.  Yes, we do want some realism in our RPing, a stab to the heart is fatal, but with the right MAGIC and blessings from a Goddess, for example, Larka can, and has, come back to life.

Don't get me wrong here!  I'm not knocking the knowledge you have provided, it's interesting and I do like to learn that kind of stuff.  But for a high fantasy role play game such as this, it doesn't really that well.

But, this is my 2cents :)

My problem with removing leather armor pieces entirely from the shops is that some people like to mix and match their armor.  I have one character that wears plate to protect certain areas, and leather to maintain mobility.  I had a character that wore a leather gorget to protect his neck from vampires, and he wore leather because plate slowed him down too much.

I'm not saying that leather can't be good. I'm saying that leather shouldn't be treated like game armor by "reducing damage by x." Revaliir is not a game because characters don't have HP pools and Attack and Defense stats. Armor, in a realistic sense, does not work by causing enemy attacks to deal less damage; it works by causing enemy attacks to deal NO damage, but generally in very specific ways.

The issue is that leather "armor" has no base nature because it is trying to be too many things simultaneously. For mail and plate, these behave in very clear ways ways (mail is completely cut proof and plate is basically indestructible). For leather, the base nature is dependant on what type of leather it is. For example, boiled leather seems to be primarily resistant to piercing weapons (tests by the English Warbow Society notwithstanding), while buff coats tended to able stop sabers cuts.

I guess my real point is that there aren't any internal rules for what players can get away with while using leather and that's what I wanted to be remedied.

"Revaliir is not a game""Revaliir is not a game"

Rev is a Play by Post Roleplay Game, so, yes, it's a game.  We are taking fantasy characters and acting as them akin to D&D in a way, which is itself a game, so, yes, this a game.  And, if you want to treat it like a game, fine, but, it's still for fun then, not to be taken overly seriously, just for fun.

' in a realistic sense"
Again, this is a FANTASY world, realistic doesn't come into it for such things.  Bullet proof vests don't stop all damage either, the person still has in the impact to deal with, platemail can be thought of similarly.  And the thing is, to have armour that causes no damage, say a character has a full set of dragon armour, that would overpowered, and that's no fun for anyone to fight against.  NPCs are fine, but PCs, no, they need to take some kind of damage when attacked, or it's powerplaying.  Another way to look at it is, since we don't have health bars, everyone should have some kind of idea how much their character can take before they can't keep going.  That's your internal Hp bar.

"The issue is that leather "armor" has no base nature because it is trying to be too many things simultaneously"

How so?  It's being leather armour, according to how I want that leather to work, while not going beyond what common sense would say any kind of leather can handle, otherwise I'd go up a rank to plate instead.  It's leather, it's not trying to be steel or scale.

"tests by the English Warbow Society notwithstanding"

Exactly!  Because in Rev, that place doesn't exist, so we don't go by what they are saying even if you had included their findings.

"I guess my real point is that there aren't any internal rules for what players can get away with while using leather and that's what I wanted to be remedied."

Yes, there is; common sense.  Like I said, leather will help stop a glancing slash, maybe slow down an arrow, but against a stab, maybe not so well.  Beyond that, you have to go plate armour to be better with stabbed and slashing.  If someone starts saying that their leather armour can stop an arrow, and can stop a sword to the gut, and can prevent damage from a club to the chest, than THAT is power playing and against the rules.

You are asking me to do too much work. Too much UNNECESSARY work. I can't make advances for the site and items if I am constantly trying to be real life accurate (that and no one would have fun) We come here to escape real life. But you also don't realize how much work it is deleting an item, making it up to everyone, getting new icons, etc, etc, etc. It can take months to get a full set of armor or even an icon done if we're behind. I got a really small team of 3 people most of the time. We just got done with 300+ icons that we had to redo.

I understand you are trying to help but this isn't something the site really needs. This is high fantasy and you should stick to those rules when offering suggestions for the site. There are some things I can completely understand. But we've had a discussion over padded armor before and see no point in changing the leather. If you don't like it please don't buy it but the majority of the site is okay with it the way it is. Which is how we've been running things.