You can play with other people in a WOW style questing system in 100 other WOW and or WOW clone games. And frankly, having played Aion, WoW, AoC, Rift, and so on, the more premiere WoW clones if you will, the only people I see playing together in that type of system are real life friends, or people joining a group for 5 minutes to kill one thing and then disbanding it immediately once the enemy is dead without even a thanks or c-ya have the time.
I don't see how WoW quest grinding is "much more entertaining" .. lets do a compare
WoW - Get quest from NPC with minor story to kill 8 wolves, bring back 8 wolf hides. Get Gold, Armor, and Experience Points. (i.e. welfare)
FFXIV - Get quest from floating stone to kill 8 wolves (with the option for increased rewards for doing it with other people), or more recently, get quest from NPC to kill 8 wolves. Complete, get gil and experience points (i.e. welfare)
Since the guide-leve system has existed in FFXIV since day one, and creates the WOW quest / daily system which you embrace AND at least at some point encouraged grouping to complete them then all those players should have been satisfied. Since the game has lost players at an astounding rate (For a multitude of reasons) its safe to assume a portion of them left due to dissatisifaction with this play style.
FFXIV will never do WOW/Clone questing as effectively as those games do it.
There are plenty of WOW/Clone games available to satisfy that market.
FFXIV currently has an opportunity to differentiate itself from the swarm by going more towards the earlier gen MMO style (which WOW has effectively killed) as there is an audience out there who is hungry for that. If they weren't, then FFXI wouldn't still be running 9 years later, with a player base much larger than this game.
Finally - If you look at the actual design of jobs, they are built to be played with strategic position. The games mechanics lend itself much better to a camp and pull style party system, not a run around with a strategyless hack n slash zerg fest. That experience is available 100 other places.
Camp & Pull will save this game if its implemented in a way that
1. There are actually enough mobs to camp and pull
2. They don't run back to their house if they get 5 feet from it
3. Jobs are more specialized
WOW style play will never save it because
1. Instanced content has little longevity
2. This game will never do WOW style as effectively as WOW
3. They already tried it with leve's and look at where we are at.
Non instanced dungeons/worlds with other parties and risks introduced by other real people, is what makes existing content fun, keeps it fresh, and gives it longevity.
In short-
SE keep working on partying, its the bread and butter of fun
Add epic quest lines (Zilart style - now those are quests I can get enthusiastic about)
Focus on job diversity
For those that want a casual element in the game, then just let them solo for severely reduced experience points. There is no need for leve's. I can't stress how much that is just MMO welfare.