This is a function of Armor to Weight ratios on other types of gear not being balanced properly IMO.
If there is armor at level 10 that is metal that is 1 to 3 ratio like 25weight to 75AC metal chest. Why would anyone use the leather equivalent that is 20 weight to 45 armor or worse. Classes are already being penalized with low armor weight but also there is no cloth/leather chest/legs/helm/vambraces with the same ratio for them to wear. If there were say cloth chest 5w to 15ac and leather chest 10w to 30ac. Then various classes could mix and match their pieces to make a full set within the armor weight restriction. This way people would actually be running around with most of the slots filled with something rather than being naked.
As it is now, its better for a level 10 healer to wear a 25wt to 75AC METAL chest piece with a 5wt to 15AC METAL vambrace and run everything else naked. Why even wear leather at all that's not boss loot. Even most boss loot leather is worse than this. So pretty much every class is going for the 25wt to 75ac METAL chest piece regardless of class and leaving all other pieces naked unless they can fill those spots with 0weight items.
I would make all armor pieces cloth/leather/metal have the same weight ratios. Then if you want to change the stats on an item from its base, add that as a STAT + or - bonus. This way if you want to have that same chest instead of 75ac be 100ac, it would have +25 AC as a stat bonus. This would allow people to recognize it was special. It would also be easier to balance other piece stats later with +pen +hit +heals +haste or whatever you decide to put on it.
The same goes above with armor weight, I would add the reduced armor weight on a piece as a + or - stat, so that people can see it has intrinsic properties that are special. Right now it looks so boring and plain.
On top of this, there the stats being added to the game are not good which is another post entirely.
I beg to differ, I use leather because:
A) AC is kinda crap for defense
B) I prefer the stat bonuses on leather and love stacking that mobility
C) Wearing many leather affords me more bonuses than a few metal pieces
D) My main defense is to avoid getting hit
E) Most characters don't need AC as they are not taking the hits
Anyone who is not a tank shouldn't really be all that concerned with AC. This is speaking from plenty of experience tanking as a sub 100AC striker in the current hardest areas of the game vs at-level mobs.
Even as a tank, resist, block, avoid, parry, and level difference are far more important than AC, though I hear AC is supposed to get changed up.
If you have a couple of healers, you are good to go with only minimal defenses.
Tanks are mostly about being the focus of attacks through taunts and threat mechanics at the moment, and their capacity to absorb damage isn't really all that much greater than anyone else and in most cases, is not necessary at this point in beta for the content and mechanics we currently face. In addition to some bosses/names there are a few enemies that will do considerable damage to where a tank is required... IF you are actually tanking that mob.
What good does a 75 armor for 25 wt cuirass do a healer? absolutely nothing unless they are getting hit, which means there was another aspect of the party that failed first (agroing adds, breaking cc, failing to taunt/hold threat, etc.) and should be addressed rather than worrying about armoring non-tanks. But that's the beauty of the weight system, you are free to do as you please with armor not being restricted by class.
Now cms or some extra PEN or HIT is useful when appropriately not the focus of attacks.
So yes, leather is quite useful, even with the crafting system in its infancy.
Btw, my last crafted piece of leather armor was 54AC for 17 wt using the weight reduction/high dura leather and +5 cms using the threading for that bonus, So... 54/17 = ... hmm look at that 3.176 ac/wt
Wolfbane greaves are 2.66:1 with 4 cms, runner cuffs are a specialty 1:1 with 1% move speed or crafted bracers can give 10 cms and an amazing 6:1 ac/wt ratio. Pauldrons can be crafted with 2.5:1 armor (currently broken and receiving no stat bonuses)... the list goes on
So unlike your broski who is never wrong, do you care to retract any of your bogus statements? There are a lot of materials and options we haven't seen yet, but so far there is already enough hard evidence to counter your statements.