In the last days and weeks the great game FF14:ARR changed a lot for me, when I realized that most people are just powerleveling while running around in (silent) FATE groups and ignoring all the other content, e.g. dungeons.
Thus I would like to see FATE rewards (xp/seals) to be nerfed or at least having diminishing returns.

Imho dungeons should give better xp and be overall more rewading than anything that someone could achieve solo - at least this is an MMORPG, thus it should prioritize social over antisocial behaviour.

In order to strengthen the community I would also like to see that the rewards from dungeons are better the more people from your own server are running with you. This would relieve a lot of the problems that the dungeon finder generates (as the dungeon finder is not encouraging "good" behaviour that may lead to good and long lasting communities, because everybody knows that he will never ever meet the people again that he is grouped with at the moment).