I'd rather not see this type of dungeon setup released.

The biggest problem with that would be people would feel forced to level up and play jobs they don't want to play in order to get into groups for these dungeons. It doesn't seem like a big deal to those of us who enjoy playing all 3 roles, but there are people who genuinely loathe playing any other job than "X".

The devs wouldn't be forcing the players to level multiple jobs by implementing this type of content, the community would be doing it.

This of course won't always be the case, as generally it's assumed FCs and LSs are friendly enough to help and accommodate and whatnot; but that guy who only has DRG leveled would get left out of/refused by many groups because he refuses to tank and heal. Then gear discrepancies between players and gear could further cause debate and drama within groups.