I think the new zone is for people who like to farm or like the challenge of doing something more difficult then their current game play is. A lot of lvl 30's struggle with it and are having a time finding a group. We waited until around lvl 50 to do it and did not do the side boss.
We have only done the first instance and probably will stick with that. The others seem a little too long and difficult to bother with.
I am glad if you are a higher level you have to go see Prof Drake to continue the dungeons rather then have it automatically put in your book after you complete the first one.
I think the visual design, NPCs, and especially the spell animations are some of KI's best ever. It is only an area, sadly not a full world, but it is stunning. The dungeons are good too. It's really interesting & fun to play, especially the bosses, though the middle instance (Atlantea) is a bit too long. I wish the gear was better. The lack of good drops make it kind of a let down to farm. The best part is the side bosses. They are tricky but fun, and have a few nice items and reagents, though there is still mostly junk gear.