I honestly enjoyed the prepatch enmity as well, and never had any major issues with threat, so long as I had fight or flight for key moments of a fight (ie soldier/knight in turn 4) and was not incredibly out geared by the DPS I was grouped with. I never upgraded my Curtana to +1 until after the patch when I had no more upgrades to make.

In fact I had to go AFK in a HM Titan one day after the heart phase while tanking and my group cleared the content without ever pulling threat from me.

As it is now, there is next to no reason for a tank to lose threat unless they are doing something drastically wrong, or a something incredibly bad has happened (a big cure 3 on 5+ targets as an add spawns for instance).

I can understand the change for warriors since they have two buff/debuff combos to upkeep and weave inbetween threat combos, but I'd like to see a change to Paladin where I can make use of the excess enmity in an effective way as well. (As of now I can use stoneskin and riot blade to maintain my health/mana bar, but in most encounters this is very irrelevant.) They could add a third hit to the Riot Blade combo that reduced Rampart's cooldown by 1 second or something silly like that, but as it is now there's very little decision making and no chance of losing threat.

In all honesty though, I don't know if my character generates more aggro than other characters by some ridiculous character specific stat? There were a lot of tanks in 2.0 who mentioned having issues holding threat and DPS players who said x tanks can't hold hate -- and while I can understand there is some skill involved in certain encounters, the average boss fight really amounts to 1-2-3 x infinity and I never experienced any of the problems other tanks complained about.

The only real reason to improve to Curtana +1 now is a whole ~5 DPS and slightly higher limit break damage.