I don't really care about the name, but in all honesty, Daimyo Wars just sounds a bit cheesy and lackluster, if only because of the "wars" part.
Some suggestions:
M&B: Path to Daimyo
M&B: Hand of the Daimyo
M&B: Sengoku (short, sweet, and relatively unique)
M&B: Rogue Wave (loose translation of Ronin, and just sounds cool)
Unification of Japan doesn't really seem to work since we're only focusing a couple provinces.