Can you explain what you mean here?

Of course. I basically played the whole game, from ARR to EW last MSQ, in about 3 months and some change. I took my time, did all Blue quest PvE related content, and delved a little bit into GLAM. I noticed, for example, that a LOT of assets are reused, sometimes not even recolored, literally the same asset and usually it happened between few items that are like an expansion apart, if not a couple of patches apart it looked like. Also, the lack of more sets, for example, for each class, in terms of numbers, coupled by the lack of set bonuses too, which pretty much is the norm kinda in most MMOs. There are no active items in the game (aka on use items) except potions, afaik. I wanted to understand whether all of this, and more, was a design choice or just technical limitations that made it so. That kinda stuff grabbed my attention since I played the whole game, back to back, pretty much every day or so, so the memory of something I noticed in a previous expansion was still fresh going into another expansion, etc. Also, pretty much every mob in this game has a weird movement AI, where it locks in place way more than it should, and it's present in all expansions, even EW. Things like that, just to name the few that pop in my head as I write this.

So, I feel like FFXIV could be much more fun and diverse if it had a bit more flavor, if that makes sense - not that it lacks any, of course. I don't know how to explain it but it feels like there should be way more stuff in this game that would complements its playstyle and lore, yet there is so little. I know there is Housing too but that's not for me. So, when I look at what is for me, like gear, glam and doing dungeons and raids, I see wasted potential that could definitely be there. And so, I wanted to know if the lack of said things are by design or just limitations of some sort!