"It isn't a matter of 'if the next game has 50 characters, that'll be enough.' There is a certain charm to games that have huge casts of playable characters, but they tend to have issues with game balance and it becomes very difficult to fine-tune each character and have them all feel distinctive.
"In terms of quantity, we've probably already reached the limit of what's feasible. I think a change of direction may be what's needed."
Most of you read this wrong, he didn't say anything about not adding new characters to the two games, rather that they decided that the game will have the same number of characters.
No doubt that they may take some out and replace them with others that fans may want or the developers would like. Maybe there are some new elements in the two games where some characters may not fit in with what they want.
There are two games being made and will be released around the same time as each other and Nintendo being Nintendo they wouldn't have the same game on two current consoles. Perhaps they both have the same amount of characters but they may have a different roster to suit the gameplay of each.
Also with people moaning about a possibility of on disc DLC, Nintendo have stated recently that this is not something they are interested in and that their own published title will have meaningful DLC. They mess up some things but when it comes down to the DLC matter I believe they won't screw people over like Capcom do.