So far I've been pretty disappointed with how utterly menial quest battles have been (e.g. being able to go afk to take a shower, get dressed, etc. while an instanced boss enemy was attacking me and come back 15 minutes later to finish it off). In an effort to get some enjoyment out of them, I've decided to start doing them butt naked (save for my trusty eye-patch, of course). While it doesn't magically add good design to the game's encounters, it can make it possible to lose even in fights where your object isn't to save a NPC.
I have to say, as naked, I did get some enjoyment out of the lv. 25 and lv. 30 class quests of Marauder and the lv. 20 class quest of Gladiator. I actually died twice on the latter and had to strategize a little (don't forget you can cancel the echo buff like any other status effect). The rest of the quests, including the former-milestone lv. 15 main scenario quest, were a little bit harder to save.
For your pleasure (and not because I'm some kind of exhibitionist), here are some cropped screenshots of my adventures:
(Observe the NPC soloing the most difficult part of this quest in the background.)
(Swinging at the mage will get him to attack you, which ups the difficulty.)
Looking at these I can't help but think "TRUE Final Fantasy experience."