Update: Achievements in 1.20: http://forum.square-enix.com/ffxiv/threads/11099
This is another suggestion that I think has a very favorable cost/benefit ratio. I don't think it would be very hard or take a lot of time to implement, and the potential benefits are great. Epic content in massive patches are great and all, but if they take too long to implement, they can possibly do great harm as well (as we can already see by some of the impatient discontent in the game and on this forum).
As any of us who have Xbox Live or PSN can attest to, the very existence of a gamerscore/trophy system adds an incredible amount of incentive to achieve goals and do objectives that players would have otherwise ignored or not cared about.
Now, we already have an achievement system, soft of. You can see a player's history on their Lodestone profile, but no one cares about that. It's not connected to a points system, so no one cares. It's not highly visible, so you can't use it as a measurement of status, so no one cares. Assign points to the history achievements, and suddenly, people will care.
Timetrials:
I propose that the game keep track of the time it takes to kill the NMs that a player or party fights. It can then display this information to everyone on the server in an easy to find menu option. The following should be tracked:
solo times
duo times
trio times
light party (4 ppl) times
full party (8 ppl) times
That way, hardcore players can show off to all the world just how good they are and how fast they can kill stuff. It's one thing to brag about it, it's another thing to actually prove it.
The game would also keep track of which linkshell the party leader had active when first engaging the mob, so it can give credit to that linkshell as well as the players.
This gives players an even greater incentive to kill NMs aside from just the gear drops.
There is a problem that I can see, however, in that hardcore players would spawn camp NMs TOO much, to the detriment of other casual players who just want the item. One way around this is to have an NPC sell items that would force pop NMs and throw the player into an instance to fight the NM. The force popped NM doesn't drop any items, and it would only be good for players who want to "practice". Force popped NMs do not influence their open-world counterparts at all.
Once all the players' gamerscores and timetrials are easily visible on a leaderboard, make them filterable and searchable by player, class, server, linkshell, etc for great functionality.
This would inject much needed revitalization just by adding new functionality to old content. It's like a "content-multiplier", if you will.
edit:
An additional benefit of a publicly viewable leaderboard is that it'll make class imbalances and exploits pretty obvious. If you were to see a ridiculously fast cleartime on a boss, then you'll know something odd is afoot.
"like" if you like, please!