I agree sorta, they are but some of the areas are also really sparse. The desert, the white one and the last one are all kind of so-so in content although the desert effects are gorgeous and the white place has awesome music. The Jungle's the best one imo because it's so layered and well designed from a level design perspective. The first one's pretty good from a vertical design perspective.
Reading the post-game impression threads, most people are talking about the plot problems which was one of my main issues with the game, but what I'm surprised is that hardly anyone is talking about how once you can fly the game has zero level design and the whole rest of the game is just "warp/fly to this spot on the map, watch a cutscene/pick up an item/fight something, repeat" outside of one mini-dungeon in the last world and a couple of caves. I think those were the two biggest issues with the game; otherwise it does a lot right with the battle system (although I think the battle system in the Skells is totally broken, but on foot is fantastic), some incredible exploration like the jungle area on-foot, and a lot of good quests.
The interviews with Takahashi recently have been really promising though. He's basically said two things of note: 1) That XBX was an engine/HD test and he knew he couldn't handle a big meaty story while doing that so he didn't try and just focused on exploration/battles, and 2) That the next game (XBX2) will be much more story-focused and closer to Xenoblade's story/gameplay pace. Those are basically the words I needed to hear after being letdown by XBX since I went in expecting a great Takahashi complete story in one game and got an extremely sparse prologue to ta new franchise instead.
