First of all, Miyamoto has never told other people what kinds of games they should make. He has bashed games from others many times, sometimes best-selling smash hits. But watch his GDC keynote from this year. He specifically says that HE likes to make people smile, but he understands that not every game developer wants to do that.
Second, I think saying "I could do Halo" is a statement of supreme confidence, and some would say cockiness. I don't think Miyamoto should even think about making an FPS, though. I don't think he could make one which sells nearly 8 million copies.
Third... Super Mario Galaxy is a platformer where you can run around on every side of objects... Futhermore, the player controls a second object on-screen using a pointer! If you don't consider that groundbreaking, and injecting new life into a stale genre, then you have no perspective.
And along those lines... Nintendo may overuse the Mario character, but they don't just churn out 1,000 pointless rehashes of the same game... Key franchises like Mario, Mario Kart, Pokemon, Smash Bros., etc., have consistently gotten ONE iteration per console. No more. Part of the reason Nintendo can sell so many games, is that they DON'T overuse their key franchises. They could certainly spit out 3 main series Mario games every generation if they felt like it. Instead they establish NEW mega-franchises, like Animal Crossing, Nintendogs, and Brain Training on DS (the first two of which will probably be one-iteration-per-system).
"[Our former customers] are unable to find software which they WANT to play."
"The way to solve this problem lies in how to communicate what kind of games [they CAN play]."
Satoru Iwata, Nintendo President. Only slightly paraphrased.
