Well I think you have a point there. Wii is dominated by Japanese games, not that this is a bad thing. Back when Rare developed for Nintendo, they took care of the Western side of things. It was a pretty effective combination IMO. I still think its a shame that they moved to MS. They've kind of floundered under their ownership, nothing like the Rare of old.
I agree that the Wii is suitable for the FPS genre, although I wouldn't go as far as to say that it is more precise than a mouse keyboard setup, it can be just as fun, and it's certainly better than using analogue sticks. I think that Links Crossbow Training really demonstrates the potential of the FPS genre on the Wii when it's well executed. Most games thus far have implemented FPS controls very poorly, and before I played LCT, I had my doubts too, so I understand why some disregard Wii as a FPS console.
I think Western RPG's with its emphasis on real time combat would be quite conducive to motion controls. Hopefully we will see more Western developers jump ship as time goes on and the Wii grows from strength to strength, much like the DS and the third party support it enjoys today, reletive to its first few years on the market.