Unique Monsters. You know, like Territorial Rothbert, or those things which you need to kill for Challenge quests, or any normal enemy with a name which always drops a gold chest? 

Those guys. You're not just locking out the areas. You're locking out everything inside them as well, of course. So if you haven't completed the map, then you're in trouble, for example...

Like Conegamer said, this character is ridiculously overpowered. Give your double-attack gems, level up her talent that increases her attack speed, then watch the damage fly and your party gauge consistently fill up. I found her invaluable for those bosses that are over level 100: they can kill your party quickly, but by using this character you'll be keeping them toppled the whole time, making their damage dealing moot.

I prefer to personally control Melia as soon as she joins, but I ditch even her shortly after you get this character.

Ugh... don't tell me that man. Now I'm gonna hafta go back to Mechonis and make sure I did everything.

For Affinity Coins! Charge!!!

Definitely, I found her to be incredibly useful late-game, with great Arts and the right equipment, you'll be ready for anything!

No character really has a weakness, aside from maybe Sharla and Reyn IMO. Better tanks and most characters have a healing move (heck, You Can Do It!!! is better than most of Sharla's Arts...)

Sadly (I say sadly, it really isn't) you'll have to play through the game 7 times whilst killing every UM to get the maximum Affinity Coins number, 999. So you'll never have enough to link every skill, realistically. 

And I wouldn't worry about it, because you can't record which ones you've killed...so long as you've got 3 Angel Engine X's you'll be winning.

While I'm not going to go that far (Sharla's still the healing queen by a country mile), I agree that Sharla and Reyn are my least used characters. Reyn can draw aggro, but his damage dealing is mediocre and his dodging is suspect. Sharla's healing is great, but she can't do much damage at all, and once I get Melia/Riki I don't really take enough damage to justify wasting a third of my offense: the skill that heals characters post-chain attack takes care of most scratches, and Shulk/Riki's abilities are enough to handle any minor emergencies that pop up.

Pretty much the same.

My issue with Reyn is that his attack is pretty poor (the game pretty much says when it's just him and Sharla that he's useless compared to most characters), and his defence is non-exsistant. Add to that the fact that many of his Arts aren't all that great and you'll see he quickly gets outranked.

As for Sharla...yes, she's the best at healing, but YCDI!!! is incredibly good, and cools-down in next to no time. And Sharla only ever gets 1 red Art, and most are Blue, so she's next to useless in Chain-Attacks. Her Talent Art is also pathetic, as is the whole system around it.

All the characters have strengths, but these two have the biggest weaknesses.

Here's an interesting video of an area of the game which, for whatever reason, was not included into the final version of the game. It's a shame, because it looks really cool! Perhaps if/when they re-make the game, they'll put it in...:

http://www.youtube.com/watch?v=l86GCaqZuxY

I've tried embedding, but I can't get it to work, so if any of you guys can, it would be muchly appreciated!

Also, there's no spoilers of which I can see. Well, aside from musical, I suppose. The vid also mentions a couple locations, but they're mostly early on, and all are in the first half of the game. 

Unless North American sales are way off (and I mean WAY off) Xenoblade should end up with very respectable LT sales. It has passed Tales of Symphonia 2! Thank GOD!

I have been doing sidequests and rebuilding colony 6 Actually I tend to do most sidequests as I play the game, and I haven't really been struggling except that 1 boss because of poor party lineup. I've even been going back to various shops to buy intermediate spells and such, and yea. When I look at my sidequests list I'm usually 50-70% done, and the ones that aren't done are Monster/Item Quests. My motto is that when I see the right enemy I always fight him, but if I don't I fight them under my own disgression. If I feel underleveled I will fight almost anybody on my path, and I rarely avoid enemies.

If I didn't do this stuff I would be at my point maybe 3 hours sooner.

Wow if I'm going 40% faster then regular pace, then I will be done in 40 hours total. I could probably get 100% completion somewhere between 60-80 hours if my assumption of going 40% faster is correct.

Also most reviews said 60 hours plus another 40-60 if you do all side quests.