OP, you realise they have actually commented on almost everything you listed. They know all this stuff already and its all frequently asked.

1. Storage and inventory is linked to server issues and they need to figure out a fix on that before they can expand inventory further. Don't ask me about retainers cause I'm only saying what they said.

2. Yoshi P mains a BLM not a DRG. Im not sure why they decided to have such a limited set but my guess is that with the other armour sets (which should be about 4 sets total) they are adding plus the new glamours it might simply be an issue of available resources to develop sets. Making 12 completely unique sets takes a lot more time. As for the DRK black flame they found its animation looked off when mounted and such. It was a design call and frankly without having seen how it looked its hard to claim good or bad on that.

3. I agree on Choco Medica. As for the rest I think they mentioned entering old duties with a Chocobo but none of the rest. As I said before what they did say is they are working on a system where you train up a squad of GC soldiers to do content with you. Its probably still in development. Systems like that are the type of thing that get added with expansions.

4. Cant comment on PvP much but at least they are paying it some attention.

5. I agree with the parry issue. DRKs are fine. Why do you feel they are lacking? Do WARs offer more raid utility apart from perhaps the slashing debuff? PLD's do but that is PLD's thing. Egi glamours are in production but low priority. Gravity is fine. Isn't it the same radius as most AoEs?

6. Elemental Materia are a legacy of 1.0. Personally I'd prefer if they just phased them out.

7. They said that they would increase GC ranks when it actually had some solid gameplay value behind it rather than just be turning in more GC seals. Personally I expect we will see something whenever we see the 'train your own unit' thing they talked about.

8. It would be nice. Currently I think my FC just shares linkshells with other FCs.

9. They are doing something instanced in 3.3. It will basically an apartment system that doesn't require GC membership and allows things like small gardening plots.

In general though the answer to most of your points is likely one of 3 thing:

1. Didn't work well in game
2. In production but low priority or requires long development time
3. Don't have the resources available to develop and implement

Again, they have commented on pretty much most of your points already, in some cases quite recently.