And lets get one thing straight about Koizumi and his insistence on adding more story to Mario. One of the games Koizumi directed was Mario Sunshine, and that game was straight up embarrassing when it came to telling a story. You had to sit through cutscenes of Mario listening to a talking water pack that ended up displaying more character than the game's star protagonist. It was awful.
But that's your opinion. I loved the cut scenes and story of Sunshine. I was disappointed Mario Galaxy didn't have much of that going on. I also enjoyed the voice acting. I was replaying Sunshine last month and am STILL enjoying everything it had to offer. So I hope Koizumi can do things like that again. It was great and amazing and would love for that to return. It gave Mario that "AAA" feel.
Remember, that's my opinion.