In regards to difficulty, I'm sort of torn on this. When I first started playing this game I found the dungeons a lot more challenging than dungeons in WoW and SWTOR, the two games I played before this one. But as time has gone by, I feel the challenge level has dropped considerably. Expert dungeons are a snooze fest and this is coming from someone who is slightly above average. And that's being nice. I don't know if I could consider myself casual since I play the game every day and have multiple jobs at 80. But I don't do savage/ex either and don't really care about BiS gear or min/maxing so I'm casual in the sense that all I do is DF stuff.
I find ARR dungeons and trials to be far more challenging. I actually have to pay attention when I do them and not just because I can't remember them most of the time. And that sort of backs up what I said earlier about the game being more difficult when I first started playing. It wasn't necessarily because I was just learning it, but also because the content itself demanded more.
So, an increase in difficulty at max level would be welcome. HOWEVER, I wholeheartedly disagree with the common forum notion that people are just being carried and enabled a lot. I think that's overblown and exaggerated as the forums are wont to do. The vast majority of my runs are over in minutes. Everyone is silent, everyone does their job and everyone peaces out at the end. On to the next dungeon.
Very rarely do I get someone in my group who is undergeared or is not doing their job. Yes, it's happened, but not nearly as much as the forums would have you believe. This place would make you think that it's a regular occurrence and a massive problem that is severely hampering gameplay.
It's not.
SE has to be careful. They can't increase the difficulty to appease what is in all likelihood a very small portion of the playerbase (like the people who post on the forums) at the expense of the casual players who, according to Yoshi (and common sense) make up the majority. It's a balancing act.
The MMO graveyard is filled with games that tried to cater to more hardcore players.