lordvaati, yes, the red are unlockables. I don't think the Hunting Dog would be too WTF compared to R.O.B. At least, the dog from Duck Hunt is a better choice than Diskun. The dog have limbs, something Diskun lacks, and could fight by pointing at a direction where the hunter from the fourth wall would shoot at, sending out ducks for the hunter to shoot at, and throwing clay pigeons. And he is one of the most recognizable video game characters in video game history. His famous laughter would be perfect for his taunt.
drag0nscythe, it took forever for us to get both Meta Knight and King Dedede in Brawl... so it is not out of the question to add both Dixie Kong and King K. Rool in SSB4. It is obvious Sakurai is interested in Dixie Kong since he planned to add her in Brawl... so I think she is one of the most likely newcomers in SSB4.
Captain Rainbow could be added as a last-minute filler clone of Captain Falcon with some differences in the regular moves. It is more of my personal opinion but I feel he is a better choice than giving Black Shadow Ganondorf's old moveset. At least his design is more interesting than Black Shadow's.
The second trainer (Gold) should have the 2nd gen starters, not Jigglypuff, Pichu, and Gardevoir. Honestly, I think Gold and his 2nd gen starters is a better choice than Pichu. And it would be epic to see a real Pokemon battle between two different trainers in SSB4. And it would be a cool reference to the Gold vs. Red match at the end of Gold/Silver. I specifically chose Chikorita, Quilava, and Feraligatr because Gold could work as Red's rival in SSB4.
Chikorita (grass) > Squirtle (water)
Quilava (fire) > Ivysaur (grass)
Feraligatr (water) > Charizard (fire)
And I always wanted Meowth instead of Jigglypuff for a long time. Jigglypuff isn't even a starter in the Pokemon Mystery Dungeon games. I thought it would be nice to have the iconic Pokemon playable in SSB4... so I kept Pikachu and Red's starters and added Meowth and Gold's starters since they are all starters in the Pokemon Mystery Dungeon games (and to promote HeartGold/SoulSilver) and the 5th gen Pokemon (most likely the star of a futue Pokemon movie just like Mewtwo and Lucario were) to promote the future 5th gen games (possibly after HeartGold/SoulSilver come out).
mariobrouser, I removed Falco because he felt more like a Fox clone than Wolf did. Honestly, Fox does not need two clones and the Star Fox series does not need four characters. Both Falco and Wolf were added as filler clones. So, I felt it would be for the best if we lose one of the filler clones (Falco or Wolf) and I chose to remove Falco and replace him with Krystal, who have a potential to be different from Fox.
So, overall, I kept everyone from Brawl except Falco, Jigglypuff, Lucario, Ike, and Snake. I replaced these five characters with Krystal, Meowth, 5th gen Pokemon, New Lord, and Mega Man. And then I added Toad, Dixie Kong, King K. Rool, Starfy, Captain Rainbow, Tingle, Little Mac, Takamaru, Gold and his 2nd gen starters, and Hunting Dog.