Again, going to try not to get to wordy here... so I'm afraid I'll just be "paraphrasing this Quote" assessment. Yes, I had to go there. Anyways, shouldn't be to hard since my understanding of this character is just from playing Cave Story once a while ago now.
Here's my picture of the categories I'll use for assessing characters again again...
These points are for making a best estimate of their chances, although the weight of each category is still unknown at this time. Other unforeseen factors could keep the character from being added. I'll likely post this at the start of all my assessments.
Quote
Popularity
Hmm, poor Quote seems to be lacking in popularity. In fact, I'd say he's easily the least popular character in polls that we've yet assessed in this thread. I almost never see him in the top 10 of most wanted newcomers. He's a distant third to the big guns of Shantae and Shovel Knight in terms of "indie" third party, and as such is maybe just barely a top 10 third party consideration.
Importance
Quote is the main protagonist of the Cave Story series. As such, he's like many third party considerations and is the most important character in his games and represents not only a "third party developer" but the creation of a single man - Daisuke Amaya. As you can tell from the name, the man is Japanese which ties into another plus for Quote... he's not unknown in Japan. Unlike the other third party contenders, Quote is a well known indie character in Japan. Shantae is passingly familiar to some at best and Shovel Knight is worse off. Quote also represents among one of the more successful indie third party characters around. He was Shovel Knight before Shovel Knight and reopened a door for Shantae to leap out of the obscurity she'd been in since her mostly unnoticed Gameboy Color appearance. He was arguably the first big indie game to reach the Wiiware's and DSIwares out there as well. For Nintendo he has significance in that regard and he's been pretty much loyal to the company too. But like all indie characters, he has a hard time stepping out of the shadow of big names.
Uniqueness
I like to describe Quote as "hipster Mega Man". Actually, not really, but it was a similarity I saw if only because Quote is also a robot boy. Also like Mega Man, much of Quote's arsenal is projectile based. Some artistic license may need to be taken with his physical attacks as a result. Lucky for him there's basically one person in charge of Quote and I could see him being accommodating, though I'm uncertain of Amaya having said anything in regards to Quote in Smash. Either way, Quote has potential, but it may not be obvious outside his various projectiles. He's got a unique look that I think lots of people find appealing as well.
Relevance
Quote is likely not competing as strongly as Shantae and Shovel Knight in popularity currently because relevance is one category where he looses to them. It's not like he's not relevant, just not as relevant and on the popularity high that the knight and half-genie are, both of which have had games come out in the last year. Quote does seem further along than them in his history however, even though he's younger than Shantae, and may yet acquire a relatively big and well received title. That's simply speculation however and for now it seems Quote is held back a bit until something like this happens.
Representation
I'll be very brief here. Quote is indie third party, and like many third party considerations he's a representative of not only a series of games, but he also represents indie games in general on Nintendo systems, and his creator/devs. I'll just say
"sure" for Quote here. I'd rather see Shantae myself if I'm picking third party characters, but Quote has at least as much argument as her.
Limitations
Quote is indie third party, he's not as popular as Shantae or Shovel Knight, and he's not as relevant currently. Those are the big ones. The latter contributes to the former. He has more of an argument for inclusion as Shovel Knight when you consider other things though, and at least as much as Shantae. His history isn't as long as Shantae's but at least he has good history with Nintendo. Being known in Japan is also a boost for him over the others. All in all however, he still suffers from the same limitations as other indie third party characters, but to more or less extents in the categories I've used to assess them.
Final Assessment
Chance: 6.4%
Like all third party characters, and indie's in particular, Quote has little chance. More than Shovel Knight, but close to as much as Shantae if only because he's known in Japan. Relevancy and popularity mostly neutralize that advantage in my opinion however. Amaya's receptiveness and perhaps how well he knows the devs of Smash could also affect Quotes chances favorably or not.
Want: 25%
Quote is a pretty cool character with potential. I should really play his game again, or the other games even. He's just not relevant for me so much anymore and his game didn't leave quite the lasting impression although it was fun. I'm much more in support of Shantae for an "indie" third party character, and it seems I'm not alone.
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Let's guess how the thread will vote for ICs...
Predictions for Ice Climbers
Chance: 24.6%
Want: 57.9%
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Continuing to make sure that "Any NPC becomes playable" request happens before Ridley.
3 Points to *Concept: Any NPC becomes playable*
1 Points to Sceptile - (that one's for you Delzethin!)
1 Point to Bayonetta?
Edit:
Oh well, it's a whole hour later than I realized. Seems I genuinely missed the deadline. Sorry to post my Quote assessment during what's now an ICs day.