I didn't liked Dynamis, because it was to much farm for to long and so repetitively, in one word : boring.
What i miss from FFXI the most is, limbus, a whole lot of path, you can choose wich one you want and at the end once you've gathered last boss item from each path, you where able to do the mega boss and drop some awesome stuff.
And if you didn't want the awesome stuff, there was still the Ancient Beastcoin, the AFv1+1 items.
You were not able to spam it, as all others event, 3 day cooldown, so it took us month to gatherer all the Omega & Ultima pop item.
And it last only 1h~ / run, so much fun there, i hope to see that in FFXIV in a way.