Power of console is not always correlated with size of the in game world map. For example:

TES V: Skyrim : 37.1 square kilometers,
TES IV: Oblivion - 56.97 square kilometers, 1,000 NPC's
TES III: Morrowind - 24 square kilometers, 1,000 NPC's


TES II: Daggerfall - 161,600 square kilometers, 750,000+ NPC's, 15,000 towns, cities, villages, and dungeons for the player's character to explore

Linear games usually have more variety of environments, That's why linearity is not a flaw by itself. It just need to be done right ( like FF X ). However, high quality and ambitious games could always have the best of both worlds. That is something I really appreciate, especially in Jrpgs.

With that being said, It is getting really hard to resist getting a WiiU and Xenoblade upon release, the more I hear fans talk about it, the more I'm excited to get into the series (except for the story part, heh). As for FF XV variety of environments, They have already shown 4 different location that are really unique ( The kingdom, the wild, the caves and dream-like world ) so this wouldn't be a problem here as well. Jrpgs are on the rise baby

About Skyrim, I couldn't agree more. it is a perfect example of the point I was trying to make.

I very much doubt that. Monolith created a huge world like nothing we had seen before in a JRPG on the Wii. I would say the only comparable game was skyrim.

I am positively sure Xenoblade X will be bigger and it will be filled with more things to do.

Well I for one felt the hype :)... and also for X... but I'm a sucker for JRPGs

About the engine:

That however goes back to some preveious comments were people were saying the PS4X1 would have an advantage.  Think about it this way:

You are right, the L-Engine will definitly require more resources, and those resources can be viewed as constraints. Monolith Soft's game will require less resources but has less resources to begin with (as in hardware) and that is a purly a technical constraint.  We may wind up with a situation where the scope of both games are (in terms of size) are very similar... which goes back to the OP :)

The bigger question isn't why haven't you already gotten a WiiU to get into the series? (And Pandora's Tower.)

Yes, this is true, but as I said Luminous is a resource hog and Squeenix is going for the "wow" factor in graphics fullstop. (They've kind of pigeonholed themselves into this with all their promotions and aggrandizing of their engine.)

Xenoblade has never been a title for looks, wasn't even good looking for a Wii game; they don't have to nor will they waste resources on high image fidelity. They're not going to slap on the works on the title because, in the grand scheme of things, it doesn't really come as a selling point of the series nor is it much of a strength of the WiiU in and of itself. It will have good enough textures, lighting, and fidelity but the work isn't going into that as can obviously be told by the terrifying character models. :P

Those with humble begins have humble expectations, as the saying goes.

Well I would say Xenoblade goes for big picture, which can actually take fewer resources if you are clever with it. This is why Xenoblade is played in a more drawn out 3rd person than FFXV.

Final Fantasy has a lot of resources being hogged by the amount of up close detail they want to push.

Also, a game can be technically inferior but still visually pleasing; just putting that out there.

Busy life ( a lot of side quests to do ) and I don't play games as much as I used too. Not to mention that you have to look very hard to find anything related to Nintendo in my country. Nintendo isn't making an effort to expand its market here, and that is coming from someone who is in the games retailing business.

Of course.  And no one is denying that.  I think XCX (at least from the footage I saw today) really shows the Wii U's true power.  Also looking at the size of the areas and the creature, I would say that the Wii U is presenting a level of quality and scope that are not acheiveable on the PS360.   So fewer resources is right but it also has more resources than last gen cosoles.  I for one am very pleased.   In reference to the 3rd persion drawn out nature, and your other interesting comment about quest variety, I can't really comment on this as I have unfortunately never played Xenoblade... but totally respect and understand your point. 

Point taken.  And yes expectations should be reasonable.  And given what the Wii U is, I am pleased with the results of XCX.  We could quite literally have an entire thread about that saying lol.