I've been thinking about it, and I really think that if SE wants to attract the highest possible audience for the game come PS3 launch, then they should focus on the following 3 items:

Company content for both Grand and Player-run companies.
Crafting as a very relevant practice.
The Armory System as being very flexible.

For Companies, they're really going to have to make good on their promise of Company-owned housing and ships, as well as adding elaborate content for both public and private companies in order to foster a larger sense of community and purpose.

For crafting, they're going to have to get that group-crafting mechanic down as well as crafting materials and items for said private companies, and really try to make the crafters as relevant as possible without being too much of a detriment to the combat classes.

The Armory system NEEDS to retain its flexibility more than ever, as that was probably the biggest selling point for a lot of people in the first place. The whole 1 to 1 class/job thing can't last too long, as that pretty much goes against the idea of the system in my eyes. Do whatever balancing needs to be done, but the most important theme in this game as evidenced by Yoshi-P's thoughts is "flexibility" and "being able to play your way", and the Armory System is probably the most important element to that strategy.