What I would like to see at level 99, rather than a rehash of merits, is something along the line of "Character Traits". Character traits are identical to job traits with the exception that they would be universal (ie. they would apply to all jobs). It might be appropriate to only have character traits kick in at lvl 99.
How would this system work? Well I think theres many ways to implement this system in terms of progress/acquisition. What I want to propose to the game developers is more the concept of character traits as a possiblity for the lvl99 limit system.
However, here are some ideas I have on how I'd like to see a character trait system implemented:
1. This system WOULD encourage people to have multiple jobs, rather than just a few. Some people might not like this and prefer to see specialization encouraged (don't ask me why). I think the character trait system could actually be viewed as both - it could be seen both as a reward for leveling multiple jobs AND as an encouragement for specialization. For example, let's say you are a BLM and you wish to specialize in this job. Wouldnt it make sense that a BLM that pursues a career as a SCH, RDM, or DRK might augment their chosen profession of BLM? I think so!
2. This system would be invoked by a new NPC moogle who will act as a quest starter. Quests will be unlocked upon reaching certain prerequisites such as skill level and job level.
3a. Quests could likely involve collecting a ra/ex item. For example, a "Tome of Thievery" for the thf99 quest. Such tomes could be dropped in the new einherjar or nyzul areas, etc.
3a. I think it would be appropriate that the process of obtaining character traits be exquisitely difficult. Only those that are very skilled in their job should be capable of completing the quests involved. As a result, it may be necessary for some rehashed Maat style solo BCs.
4a. I would personally like to see 2 different sets of quests. One set of quests would be triggered by having a job at LVL99. I would be quite happy with something as simple as a maat rehash - farm a ra/ex item in new content then go to such and such BCNM and do a solo fight on the particular job. The reward would then be a character trait that is related to the quested job. I don't need to give examples... its pretty obvious what it would look like.
4b. The other set of quests, perhaps more interesting, would be triggered by skill level. Having capped skill (capped on a job that has A-A+) would unlock that skill's quest, which could either be a lame weapon-points quest, or something more creative. The reward could be a damage/accuracy bonus for that skill (if its a weapon), or some enhancement of the magic/defense skill.
5. Ultimately, I think this concept has a lot of potential. It provides a reward for experiencing more of the game (ie. playing different job classes) and integrates your accomplishments in a way that most people would find appealing. Moreover, the system could easily be expanded upon over time, 2nd and 3rd tiers could be added along with new content to allow characters to continue to grow. Looking years ahead, I think this sort of system might be essential to keeping players interested... because once players feel like they cannot become more powerful, they start to lose interest.