Ok, the slosher deco is pretty great. But before discussing the kit, an interlude on slosher mechanics:
Slosher shots can curve! I don't mean the trademark vertical arc; I mean laterally. And more than just a few degrees- I can get approximately 90 by whipping the gamepad around. While that extreme may be impractical, don't be quick to dismiss this in general. In my testing sessions, I can easily line up a clear miss, fire, then rotate my reticle while the paint is in mid-air and strike my target with the middle of my bending stream. This is definitely applicable in a firefight.
This is of course a result of video games generally ignoring conservation of momentum, going back at least Super Mario Bros. You shouldn't be able to jump out over a chasm then pull back in midair and land where you took off. Similarly, once you hurl a glob of ink from a bucket, you shouldn't be able to influence its trajectory. But you can.
Anyway, back to the slosher deco. It didn't give me the instant sense of joy of the tri-slosher, but it feels well-rounded and powerful. This is my first serious go with the splash wall- it obviously excels at controling space, but there's a learning curve as to whether to toss it or just slosh. Kraken fits in well, though I still don't love it except as a panic button. Strangely I sometimes feel lacking in range compared even to the tri-slosher, with which I can at least toss a disruptor into a sniper nest.
As to gear, priority should probably go to ink efficiency and ink saver sub in particular. Though it gets a bad rap sometimes, ink saver sub is doubly useful here because you can't start refilling until the draining animation completes. I've considered swim speed but it doesn't seem to make the kraken that much faster. Perhaps quick super jump for kraken bombing?