Familiars and Armor

So with the recent Blog and FAQ change I am still a bit confused on how armor works for Familiars despite some other threads with similar questions. Prior to this I know that Familiars and Animal Companions alike had access to neck slots and armor (barding) slots. But this seems to have been taken away from Familiars while Animal Companions get to keep it?

I'm confused about three things on this:
1. What about non-magical armor? Can a Familiar still wear a Mithral Chain Shirt?

2. Why was this change made specific to Familiars? If someone were to have asked prior to this change which is more powerful to allow armor on Familiars or Animal Companions I think we all would have said Animal Companions. Personally, I didn't see a problem on either side of it. But with the change the Familiars get hit with the nerfbat and Animal Companions are left how they are? It seems like an odd choice from a balance perspective.

If it wasn't for balance reasons, was it for flavor reasons? Was it designed with Wizards using Mage Armor on their Familiars instead of getting them armor?

3. The specific circumstances I am concerned with are for a character that I have. He is an Eldritch Guardian Fighter with a Brownie Improved Familiar. Prior to the change rules were still a bit fuzzy on what he could use. Now the rules have changed but there are still some questions.

If I understand things correctly before he could have barding (armor was still a bit unclear) and a neck slot item. He could also use an Ioun Stone but my character would have to set it spinning for him. Now it appears he can wear non-magical armor (but not magical?) and lost the use of a neck slot and the rules are now silent on Ioun Stones or other slotless items. I'm guessing that my character isn't the only one affected by this change.

I imagine a lot of people had neck slot items for their Familiar. Less of them probably had armor as most Familiars are Wizard's Familiars or classes capable of casting Mage Armor. But what about my Fighter? Even though he shares feats with his Familiar (including armor proficiencies), is more martial than probably any other class with a Familiar, his Familiar can no longer wear magic armor? And if he had it previously it just... falls off? But he can wear normal armor with no issue? I understand that he could take the Extra Item Slot feat to allow him to use it but I already had planned on him taking that for the Belt slot which he will need (both the character and Familiar are archers).

I'm not left with a lot of options here, I think. Without being able to cast Mage Armor I could have him wear non-magical armor but can never enchant it. With Familiars not having scaling AC and Dex like Animal Companions do and only gaining half the benefit to AC from armor from Tiny size that isn't going to keep his AC relevant. Lack of a neck slot prevents getting his natural armor higher. It isn't like his AC was stellar to begin with.

...I guess I just feel like the loss of armor for Familiars was an unnecessary nerf. I'm sure it has something to do with feeling like it hit my character harder than most. I don't suppose leadership would consider giving them the armor slot back?

Also there is the logic thing. I know it is sometimes controversial to bring logic into a Pathfinder game. I think I can't put it better than BNW did in the other thread:

Thomas Hutchins wrote:

Linda Zayas-Palmer wrote:

If you have a saddle or armor slot, you can definitely wear mundane saddles or armor without taking Extra Item Slot

link

This seems to be saying that familiars with an armor slot can wear non magic armor

... they are either making this incredibly weird or explaining it very poorly.

Full suit of plate armor on a weasel: no problem

Enchant it... ERKS! It won't go on....

???

Bump.

...I can't be the only one affected by this and confused by the new rulings.

Partly it might be that not everyone has noticed the change yet.

Partly though I think you're in an unusual position. You're using your familiar to actually fight (instead of for bombing runs, wand use, or stat boosts), and your character can't cast mage armour or shield.

That said though, your problem seems awkward. I don't have a solution, but you have my sympathy.

Another thing is that question 1 was already answered and most people don't know the answer to 2 of why was it done. And 3rd wasn't a clear question, but yes they can still use slotless items like ioun stones since I saw that asked somewhere in your paragraph.

The other thing is that there are a few questions about that FAQ that need to be resolved and have been mentioned that they'll be looked at. So since there's been nothing new on it yet (dang holidays and people doing things other than answer our questions ;P) we have no further insight on if anything will change.

EDIT: BTWs the fighter does not share it's class proficiency with it's familiar. So the familiar does not have armor proficiency or weapon proficiency unless a feat was spent.

FAQ
"Despite wording in the Armor Proficiency feats, fighters (and other classes) have a class ability that grants proficiency in those armors--it doesn't actually grant those specific feats."