So let me go over these one at a time....
1. Requires far too much memory for the servers (and what sane person wants metallic bright orange?).
2. If they've stated that it can't be done, then odds are that it -won't- be done.
3. Addons are are usually a massive can of worms. Making such addons means that they might be required for certain aspects of the game, which means downloading those apps from some third-party site, which would make it easier for hackers to latch viruses onto said addons (like idk, a trojan virus) and make it that much easier to hack your account. Sure, it might help those people, but so does learning how to play.
4. I'm opposed to this mostly because I find the people wanting their precious elemental ponies to fly to be far too annoying for me to tolerate.
5. Not quite sure which percentage you're referring to, but I'm fairly positive that the idea for the skill is to be cheap, so the reward should be equally so.
6. I agree with this point except for overmelding. That deserves to be a far slimmer chance.
7. Again, requires far too much memory for the servers. As for selling homes, just because the seller doesn't make a profit from the base land sale doesn't mean that they couldn't add some surcharge they themselves could enforce.
8. I'm more convinced that quick synth was never meant to be a thing, although it could just be that it takes about as much time for the servers to process an auto-craft order than it does for someone to manually process it.
9. Grade 5's are supposed to be super rare, right? Yeah, I thought so. As for diadem, it'd make more sense just to make it an open-world daily/weekly hub like what WoW has done in multiple expansions.
10. In the future, there might be more ways of getting umbrite, but probably just the crafting option just to ensure its rarity.
11. Not sure what you mean with "specialization perks" with the non-crafting classes, but I know they might wanna improve DoH specializations first to make them feel more um....special?
12. You mean like those calendar events WoW rotates? Sure, sounds good enough.
13. There's already the fluff from the veteran rewards, so probably won't happen.
14. That one actually brings up a good point. Big casino and no slots? Maybe Eorzea doesn't have enough old chainsmokers that would gamble away their retirement gil.
15. Pretty sure they expanded the limit to keep you from wasting your entire day on them. That being said, it probably wouldn't hurt to expand that number a bit if they're gonna keep adding new beast tribes while still requiring stuff from the old ones.
16. I kinda agree with this one, but it should still list which class it requires you crafting it on. Generally speaking, the whole crafting list UI needs better organization, but this point would be a good start.
17. This makes me glad that I know people who have CUL maxed out that know what foods to give me for stuff. Fairly positive that this is another memory issue, but I'm sure there's some website that has a list setup for in-game food based on stats.
18. Sure, but to be fair, shouldn't you know what minion you want BEFORE you check the marketboard?
19. Once again, another memory issue, but thankfully it's just a nuisance and nothing really outrageous.
20. The only reason why summoners can spread their dots is because that's their primary AoE since they have nothing really spammable on that end. Bard, on the other hand, does have a somewhat strong spammable AoE on top of at least one other AoE, so dot-spreading for bard probably won't be a thing.
Couple of good ones, but the rest seem like complaints regarding technical limitations that currently can't be fixed or thoughts of someone who came from WoW or Rift or some other game with better customization.