Come on Nintendo. Make a Cia and Lana amiibo. Come on. Come on. Come on.

I think Nintendo needs to have the amiibo always unlock different costumes/skins for games, along with the other features. People pay a lot of money on online games for that kinda stuff.

http://www.youtube.com/watch?v=31g0YE61PLQ

In all seriousness, Amiibo Unlockable Content (AUC? Can we call it that now?) can potentially be a really good deal, "can" being the operative word. If you use Amiibo to unlock content in 10 games, that's a little over a dollar per game. That's not that bad when you consider that most Nintendo fans even mildly interested in Amiibo probably buy more than 10 games across two platforms (sometimes even only one) and then the Amiibo is likely also available for games on future platforms. At the same time, you would need all of the applicable figures to get everything. It would be nice if you could just go to the eShop and buy the same content à la carte if you didn't have the specific Amiibo. While some people would prefer Amiibo not exist, this would be a good compromise if Nintendo insists on this content unlocking method. It's kind of weird that in the long run, going the Amiibo route could end up being the more cost effective option.

Having the ability to buy the content from the E-shop without the figure would get rid of most inclination to even buy the Amiibos.

"Wonderful idea, buy a Pikachu amiibo, you can dress up as Red or Green from Pokemon Leaf Green/Fire Red in Pokemon X or Y. Or you could pay like $1-$2 for the costume, but you won't get this awesome figurine!"

Yeah, most people will go with the $1-$2 route. Having the skins exclusive to it is fine in my opinion. Its something worthwhile to a lot of people, but its not mandatory. Not to say I discourage more skins available for sale on E-shop, but exclusive amiibo skins should stay that way. Its not screwing people over horribly.

Not necessarily. Buying an Amiibo could potentially unlock more than $13 worth of content. At that point, you really just have to weigh how much the upfront cost affects you. Also, I haven't heard that Amiibo are locked to a single piece of hardware meaning if you have a bunch of friends, all with different Amiibo, you could unlock a whole ton of stuff among your group.

Except we're not just talking about skins.

What are the other features? That will depend on the game. As stated in the article, in Hyrule Warriors, the Link Amiibo nets you the spinner weapon. Having the content available by another means opens it up to more people.

Depends on how much Nintendo invests into this though. I'm not expecting any Amiibo aside from the Mario ones to expand across very many games. Who knows though.

I'm specifically referring to skins though. The other content is just really underwhelming. I wouldn't even invest 50 cents into that.

Unlockable amiibo content through the E-shop could be debated, but that would kinda contradict the entire point of Amiibo. Can you buy the Skylanders/Disney content via E-shop or is it exclusive to the figures? (Serious question, I don't know if it is)

Of fucking course they all do. God damn it Nintendo, I don't want one of your fucking plastic dolls and I really don't like being punished for that.

The difference there is that Skylanders/Disney are based entirely around toys. Nintendo's games appear to be along the lines of "supplementary material", i.e you do not "have to buy" any of them, you get complete games with or without them.
If you really care about having every single piece of DLC then you're probably the kind of person willing to drop $15 on a figure to get it. Don't like the figure? Unlock the DLC then give it to your baby brother.