Hmm, I really can't understand why so many people is scared by repop time. Do you fear to really be forced to wait doing nothing?! It is not necessary the case.

I don't mean the waiting time makes a fight difficult, but it afflicts how much practice you can do over that, and how epic would be your victory. Spamming an HNM with 5 minutes repop means that, even if you don't have fingers to play, at the end you will win it.
If you can combat against it just once a day (If you pull it), it means you can't and you don't want commit any errors, because you are fighting a RARE mob.

My opinion is that there are two different concept behing HNMs through the people:
  1. EX Final Fantasy XI players: Long Repop Time
  2. New Final Fantasy XIV players: Epic Fights
These two points of view don't exclude each other and can cohabit too. We can call High Notorious Monsters the FFXI school of thought, and F.A.T.E. the new one.

Even if it appears F.A.T.E. could be not so much hardcore, it's a perfect system to improve which can get big attention by players. In A Realm Reborn both systems could be improved, but the secret is not to make one more worthwhile than the other.