Reducing the Hit Point total of Absolute Virtue did diddly squat towards reducing the difficulty of the fight. Absolute Virtue could have had a grand total of 5,000 hit points for all the good it would have done people... the thing at the height of it's power could literally spam any and all 2 hour abilities of all classes except those found in the Treasures of Aht Urghan Expansion. That includes the one that instantly restores the entire parties hit points to maximum! And imposing time limits on Super Bosses actually INCREASES the difficulty of the fights, not decreases the difficulty. Can you imagine fighting Ruby or Emerald Weapon in Final Fantasy VII if you were limited to only 10 minutes?
Now if you're going to cite the Pandemonium Warden Fiasco, you need to explain what all the bad press was about, just in case there are people here who don't know.
The problem with Pandemonium Warden was that Pandemonium Warden is a Tiered Boss. What this means is that he is identical in nature to bosses such as Chrono Trigger's Final Boss for example. Pandemonium Warden has around 12 or so (not the exact number) different forms. Each of these forms is followed by a group of other enemies that provide support for the boss during the fight. In one of these forms he is followed by a group of White Mages, who again can each use the 2 hour ability that instantly restores all health to a party.
The problem that caused all the bad press relating to that boss, was that one Linkshell had attempted to fight Pandemonium Warden as a World First. They weren't really prepared for what the boss had in store for them though. Cue 18 hours after the fight had started (that is 18 hours of fighting a single enemy), and they had just defeated the latest form, and they all thought they had won the fight, their adrenaline was actually beginning to wear off at this point and these people had more or less been in front of their computers for 18 hours straight at this point running off of a sugar and adrenaline high... low and behold another form pops up 5 seconds later. People promptly begin to pass out from Adrenaline and Fatigue Sickness, which isn't something people want to experience after doing something like that.
Point is, the fight and subsequent fainting spells received a crap ton of press time, and that is what cued Square-Enix to weaken the vast majority of their Super Bosses and / or impose time limits on them. And it is because of this reason that we don't have the Notorious Monster System, or Super-Bosses like that in this game.
In fact, the closest that Final Fantasy XIV: A Realm Reborn comes to a true Super Boss (in the iconic sense) is the Odin and Behemoth FATES. And those aren't even remotely close to comparing to the Super Bosses produced by the rest of the MMORPG companies. Until you have fought Tequatl, you really haven't seen a modern Super Boss.