There's nothing wrong with taking things from other mmo, especially if it works. But they need to understand the how and why behind it, as well as actually making it work. If I think back, most everything I can say about their game features are lacking in innovation or dynamics, but could've done much more if they had put the time and/or resources into it.
-FATEs? Dynamic events are great. Hell, WoW even does this now for WoD; I'm only in the first area and it's a hell lot more diversive than what we have in FFXIV. The former has you doing various objectives at once which gives considerable amount of EXP and currency, but in return they're a lot more scarce. The latter has them in such numerous numbers, but they're all essentially "kill X" "kill boss", and 'gather item" and give relatively low exp compared to everything else that is available. It's so easy to burn out and see the repetitive nature of it when you slam your head at it when you run out of quests. And don't even get me started on FATEs being required for CT, animus and atma.
-Raid, I don't mind the fact they tried to make more than one difficulty mode, but again they seemed to have misplaced what the players actually want. They overshot who the appeal was supposed to hit, and I feel that some servers have taken an unrecoverable hit as a result because of the mass transfers. Their raiding formula seemed to have worked for coil during 2.0; midcores were able to clear, hardcores cleared within a week, casuals would eventually get in as the content gets nerfed and still has the novelty of new content, at the same time, savage mode savage was still there. Come 3.0 they skipped stepped 1 completely and right into step 2 and 3.
-Diadem. Again the concept was great, execution leaves a lot to be desired. I'm damn sure they did not want this to be a 90 minute grind fest because the other aspects of it become under utilized (caves, open-world spawn triggers) or does not necessitate an actual party cooperation (gathering/fishing).
To me, 3.0 in general has been pretty disappointing once you get past the novelty of it being an "expansion"...if you can call it that after you get through the level cap. Other people have said it and I'm starsting to lean toward it, it feels like a patch we paid for rather than a honest-to-good expansion; there isn't much of new gameplay changes, the new jobs (esp AST on release and MCH compared ot BRD) feels really meh, especially when you consider that they added ninja in a content patch, not an expansion and pulled it off fairly well with it's own identity. While it had problems with numbers, those can be easily tuned with hotfixes, at least compared to trying to dehomogenize BRD and MCH's gameplay (unless they intended for that, which I don't feel is the right decision when it comes to adding jobs)
Combine that with the fact they, by their own admission, is adding less content from what we have now (dungeons, trials, story) to implement more new content (LoV, diadem) and flunking the former, it just leads to a very, very broad game with no focus. Once get past the novelty of it being "new", you utlimately go back to doing the same thing. I've honestly felt like I've exhausted what 3.1 has to offer after a week, sans farming thordan weapon for my other jobs that I probably will level out of boredom (which I did in 2.5 before 3.0...so welp)
The circumstances behind the two content are entirely different though. SoF was DF content that needed to be completed to progress. People were not willing ot invest into the time (and still won't) if they got it in their trial roulette because of the liability of the fight when you have to wait 10 minutes for a reset on an unrecoverable fight. Heck, farming SoF wasn't even a thing. Same with ultima dropping I80 rings when Myth rings were available since the patch before ultima's bane.
Thordan on the other hand, is not DF content and drops i205 weapons. People would still be farming it the same way they'd farm Ravana (even when eso weapons were out, some would like to gear their alts). This would still be the case if Eso is still weekly locked and they added gobdips...espesically for MCH who has a rather garbage eso weapon that is honestly not a good upgrade (if not a downgrade for some people) to heavensfire.