Zelda, Metroid, Pikmin, and yes, even Pokemon would have their M-rated counterparts.
M-rated Metroid? What's the point? So it looks exactly the same but has swearing and blood in it? Metroid doesn't NEED to be M-rated. It already has a mature style and it does it without being exploitive. A "mature" game doesn't have to mean a game with a literal M-rating. It just means a game for an older audience and the truth is you could do that with an E-rating. You know why Resident Evil is full of gore? Because it fits the subject matter. I'm sure some people would think it's exploitative but it really isn't. Metroid's subject matter isn't such that it would really require anything that would earn it an M-rating.
As for the others I think I would prefer to just get new games. I don't have any problem with those games the way they are. In fact I love all of them. I just think Nintendo has a little too many cutesy games and could balance it out better. I think in Zelda's case they took something that appealed to an older audience as well as kids and overcompensated on making it cuter, thus alienating the older audience.
We've already seen them appeal to older gamers, now everybody's whining that 30+ is too old.
Ah, my least favourite type of argument. The "THIS IS WHAT YOU WANTED ALL ALONG!" The Wii ____ series is very much like Nintendo's "kiddie games" of the past in that they're technically inoffensive enough that everyone COULD like them. But the same problem persists - those that want something more specifically tailored to their tastes find themselves disinterested. I was open-minded enough to play Nintendo's cute "kiddie games" because I recognized that the gameplay was still fantastic. But I could sympathize with those that were put off by the setting, and I noticed the games that didn't try so hard to be for "everyone" were personally more enjoyable for me - Goldeneye/Perfect Dark on the N64, Metroid Prime games on the Cube. Non-games take it a step further and the actual GAMEPLAY is designed to be technically appealing to everyone. For me that was what kept the so called "kiddie games" from being unplayable. That was the one thing you could rely on with Nintendo games.
True variety doesn't mean "every game for everyone". Nintendo has NEVER figured that out and if they wonder why "kiddie" has been replaced with "casual", that's why. True variety means you have ten games aimed at five audiences and each of those games is very specifically tailored for the target audience so everyone gets two games they REALLY like. Nintendo's method was and still is ten games for five audiences and they make all ten something that all the audiences COULD like but in the end the only one that is truly satisfied is the lowest common denominator.
What are your tastes in movies or music like? Do you just listen to top 40 pop music and watch the big mainstream "number one movie in America!" films? Or do you also have some specific tastes? Some stuff that's more obscure that you don't expect everyone to like but you really like? What do you find more rewarding: the mainstream pandering "everyone COULD like this" stuff or the more specific stuff that feels more like it was made for YOU?