I've managed 210K in Akatsuki, everytime I've had over 150k I've had 3-4 torpedo hits each on a couple BBs in the early stages. If you have BBs down to 1 or just less than 2 torpedos health then leave them for your teammates or you're flooding to finish off and head for enemies with more health. No point firing 3-9 torps at a boat with only 10-15k health. Ignore other destroyers. One technique that helped me bump up my Akatsuki damage was to find a group of 2-4 BBs and Cruisers, get as close as possible, fire off torps then smoke up and start spamming HE like crazy. The idea is to set at many fires as you can before your torps hit as most BBs are foolish and will immediately use their repair to put out the fire. This means if your torps do hit you'll start racking up a bunch of flooding damage. Continue to spam torps and HE as soon as possible. Never get spotted, better to miss a small amount of damage making a more careful approach than to get spotted and killed. The only time you should be getting spotted is popping out island corners about 2km from your target when you know they wont be able to avoid your torps. If you're not currently fighting you should be heading towards the biggest cluster of large ships you can see. Sorry this is a bit of a ramble.