I think Microsoft should buy out more eastern devs. Realisticaly they should try to acquire
Blue Side - They make games like no other company does and MS always get some love from this studio.
Valhalla Games - Itadaki loves the Xbox and MS could get some of the most over the top games from the most over the top dev from Japan. Games from him are alway unique and being exclusive could give a lot of style to the 360.
Cave - They make Shmup like their life depends on it and even if Xbox gets no love from japanese gamers this dev seem to love making games for the Xbox. It could grow a very niche audience exclusively on XBL with all these weird cool looking shooters.
Mystwalker - I don't play jrpgs anymore (all because of Bioware and Bethesda) but a lot of people do and at the start of this gen the 360 was the place to get them... MS should've bought that studio and have them continue with the sequels of Blue Dragon and Lost Odyssey.
Edit: typo
