Quote Originally Posted by al Roumi View Post
... The trick here is picking the weakest opposition and the opposition you can hit hardest. ...
While I agree with @al Roumi when the situation hasn't changed that much from the starting positions, I wouldn't go this way when 1 faction has conquered a sizable piece of Kyushu before you're done with both nearby islands.
In my case Shimazu rapidly conquered All but 4 provinces on Kyushu and was still going strong. However, the hard economic reality also applies to them so they couldn't support big garrissons on all their provinces.

- I allied with my only land neigbour, who was already under attack but seemed to be able to hold out for now.
- I sent an Ishin Shishi to Shimazu frontier provinces to start revolts. This should divert some of Shimazu forces away from your ally. For the most part, the revolt seemed to destroy reinforcements and little else.
- Muster a sizable force and land behind enemy lines. Priority towards weakly defended provinces with a great significance to Shimazu.
- Having the strongest navy will protect your own shores.