And with that I guess we are done.
Sub, I get what you are saying, even though some of it is wrong, I get.
You main a marksmen and you are tired of AD champions bursting you down faster then anyone can pop a balloon, I understand. What you have to understand is the nature of the class.
The Marksmen class is a squishy, high dps class that is only useful when going full damage-- be it AD, Crit, or attack speed.
The way the class is 'balanced' is by making them easy to kill in exchange for their high dps. The way the marksmen class raises their survivability is by having a skill that physically moves the character out of harm--- Graves, Lucian, Kalista, Tristana, Ezreal, and Corki-- all have an ability (or passive) that can move them out of danger. Other cases like Sivir, Ashe, Jhin and Jinx are special but they still have a form of surviving. Sivir has a spell shield, one of the only two champions to have such an ability, while the other 3 have CC, something rare for the marksmen class. Then there is Cait who has both.
In Class design, they are meant to be easy to kill once you can get past their one method of surviving. In item design, they have another form of surviving: Life Steal! Life steal is the only in game sustain marksmen have.
Speaking of items, lets talk about a comment of yours: "Marksman are in horrible state and one reason for that is lack of itemization."
I mean, sure... MF, Jhin and Varus seem to be everywhere I go, Vayne is still good, not to mention Ashe and Jinx but whatever. I can't argue if they are in a good place, which is better then mages, but whatever.
I can argue the "lack of itemization" portion. Marksmen, as a class, can build the following:
I) Attack Damage
II) Attack Speed
III) Critical Strike
IV) Life Steal.
Now granted, most of these double dip, Attack Damage and Life Steal, and Critical Strike and Attack Speed but these are still options.
A marksmen can go AD without Life Steal, there are plenty of items. Thus, when they do get Life Steal, they are getting Life Steal and the AD is what helps its effectiveness. Same applies to Critical Strike and Attack Speed, but with the Item Infinity Edge, you can tell if they are going Crit or attack speed.
That there is four stats of items Marksmen can go for. Now Granted, not all marksmen are the same and some should go for two stats over the others. Jinx, Cait, and Ashe are great examples of champions that should go for crit and attack speed over AD, while Graves, Lucian, and MF are champions that should go for AD. Both of these groups can still use Life Steal, however.
Compare that to mages, who have only one, arguably two, stats they can only use: Ability Power and Mana. You want to talk about limitations, look at mages. They want armour, Zhonya's is the only option. Magic Resistance: Abyssal Scepter, only option. That is it! They want to survive, they must rely on their kits from their on.
The counter argument could be that with in Ability Power, they have some options to really stop and assess the situation with, where as Crit, Attack Speed, and Life Steal is pretty straight forward.
The thing is, Life Steal is not straight forward, each life item behaves differently. One gives you attack speed, another an over-shield, while another is the best healing in the game... But the champions that use AD have a bigger variety of what they can use, even to the point of using items that were never meant for them.
You mentioned that Banshee's Veil was meant for Marksmen, which I have a hard time believing in. Given the stats, this is an item that few marksmen would actually be useful for the class. Like I said, the marksmen class is a dps class, and this item does not assist with the dps part at all. Now granted, I will give the actual passive, the spell shield a fair go because any champion can use a meaningless or low cd ability to pop that on a tank but it still does not fit the class itself.
What I can tell is that items like Maw of Mal and Edge of Night was meant for AD Assassins against mages. Mercurial Scimitar is indeed a item that was meant for Marksmen but who ever gets this item? (Thinking to myself, is this item even for Rift? That is how often I have seen it, I am doubting if it is even for the map. Checking, no it is Dervish Blade. Okay) Then there is Wit's End. That could be used for Marksmen, if they have magic in their kit, otherwise it is a support item meant to increase damage for an ally, like before Pre-Season 7 Banner of Command on tank supports. I would argue that item is more helpful for Diana or Ekko to increase their own burst when they engage and deal a few auto attacks over most marksmen. Point is still ONE item was 100% meant for marksmen for the stat MR. Wit's End is debatable. Every other item was meant for the assassin class. Oh, but wait!
You get champions like MF and Varus who can use these items and screw up the whole meta. What was suppose to be for AD assassins is now getting to the point where AD Casters use it, making us go in a AD Caster Meta, which is why you say some marksmen are in a bad spot: "Marksman are in horrible state" because most are not AD Casters.
Most of them use auto attacks to deal 85% or more of the total damage dealt in the game. Jinx, Ashe, and Cait are great examples. Granted Cait has a Q and a good damaging ult, most of the damage is coming from her crits, an auto attack proc. Marksmen are not in a "horrible" state. They are having a shift from Mrs. and Mrs. I-Don't-Even-Need-Abilities-Other-Than-My-Q Ashe and Jinx to Miss, Mr., and Mr. Attack-Speed-Is-Fine-I-Guess-But-What-I-Really-Want-Is-Attack-Damage Fortune, Varus, and Jhin.
Analyze the game! DPS Characters are not suppose to have even decent armour and magic Res stats, they deal damage from a safe distance. Granted, there are plenty of times where you get caught out or an assassin wants to dance in a 1v1 and your dps doesn't mean anything if you can't respond in time, which is a skill that grows.
I would have liked to actually talk about the AD/Armour item more but I think targeting the class and the problems is better for you. I am done. I would have liked to have a genuine discussion and talk about this but because you had to go into my profile and mention that because I have had recent ping issues and do not wish to cost my team a game and thus have been on bots and generally screwing around on the new testing mode does not mean anything. Ethos have nothing to do with this. Granted it would be nice to have some, but logos is what matters here and I had tried to present it to you, but you had to commit the Ad Hominem Fallacy and so I am done. I mean sure, I could continue knowing that my argument is stronger because you had committed said fallacy but I think you are in no place of reason since you committed it and so I am resigning.
Having an AD/Armour will screw the meta more. It WILL make AD Casters stronger and will not be for the good. Having a MF, Varus or Jhin with Edge of Night, Mal of Maw, this AD/Armour item, presumably Beserker's Greaves (or whatever Jhin wants), Life Steal-- Death's Dance or BloodThirster and a Black Cleaver will make them powerful as heck. It will not make other Marksmen shine and it won't make their be balance in the class. It will screw up everything. That is all. Try to get far in life committing fallacies.