As Sakurai said himself, it takes sufficiently less time to alter the appearance and moveset of an existing character than to create a new one from scratch. The effort it takes to make a clone is roughly an 1/8th of that of a new character, meaning that taking out those 3 wouldn't give you a new character.

The original is gone, somehow. Also, I'll ask this again:

Am I the only one who is sick of the "Wasted Character slot" bs? Especially now that we have DLC characters. Plus, I personally like Dr. Mario returning.