I know I am considered one of the biggest clone haters around here so hear me out on this one. I personally don't mind the concept of clone characters that much since every single fighting game has at least one character that is a clone of another (Ken is perhaps the most famous clone character of all time and the MK series and the Namco 3D fighters are riddled with them). However, I HATE clones when...
1. They are used to easily expand a roster
2. They take the place of a much worthy character
3. When they don't make sense at all
Melee is guilty of all three. Its common fact that Melee was only going to feature 5 secret characters. But the team decided to add more characters to the list, but there wasn't any time as Nintendo kept rushing them so they decided to take existing characters and make clones out of them. I know clone defenders keep saying that creating and balancing characters isn't easy and I agree. However, between making a brand new character and creating a clone based on an existing character its clear that making a clone is FAR easier. The clones were a product of a rushed development cycle because Nintendo NEEDED the game out by Christmas. So in all honesty, as weak as the 5 secret characters were I would've preferred to have the roster end there than to expand it with cheap characters.
Second, they should have used more worthy characters. Take a look at some of Brawl's newcomers; Wario, Pit and Metaknight. Fans wanted them playable way before Melee was announced so why didn't the team take some time to make them and make fans happy? I don't recall anyone saying "Gee, I sure hope Dr. Mario is a playable character!" or "Young Link should be in game, even though Link is already there!".
Finally, many of the clone characters didn't make sense AT ALL. I understand Falco and he was a good alternative to Fox's insane speed. Pichu, sure. Roy? I'm not a big fan but he was decent. But Dr. Mario? And Ganondorf a CAPTAIN FALCON clone?? With Dr. Mario that means there are THREE characters with the same moves. Luigi makes sense as a Mario clone since that's how he was always portrayed, but even they had the right idea of making him a little more unique. Dr. Mario should have been an alternate costume, PERIOD.
And Ganondorf...I don't need to explain it. He was his own character so it was VERY weird that they made him a Capt. Falcon clone. Same deal with Young Link.
So in short, I don't mind a couple of clones here and there as long as they make sense. However, when they take up half the roster and they don't make sense THAT'S when I get angry...
Which is why I think Brawl will not have that many clone characters. With the team having more time to work on the game, the newcomers list being big (and likely to grow each day) and the many new characters that have been suggested it looks like Brawl's roster might be very varied and unique. So if they make a lot of clone characters once more then I'll second S_B's idea of mailing fire ants...