As in every other facet of plastic modeling, it's tough to make simple generalities. Generally speaking, all the manufacturers have gotten better during the thirty years or so that they've been making warship kits.
There are two brands with which it's hard to go wrong: Tamiya and Skywave. The best of their kits are about the best that exist. Recently Tamiya has been retooling some of its older warship kits. The new 1/700
Yamato is pretty spectacular.
The recent
Takao-class heavy cruisers from Skywave are also excellent, as are any of that company's Japanese destroyers. If you're interested in an aircraft carrier, possibly the best ones on the market are the Tamiya
Shokaku and
Zuikaku. The Hasegawa
Akagi and
Kaga are older kits, but basically sound - and capable of being turned into real masterpieces with the help of aftermarket photo-etched parts (e.g., those from Gold Medal Models).
If you're interested in an earlier period, a small firm called Sealsmodel makes an exquisite model of the
Mikasa, Togo's flagship in the Russo-Japanese War. I'm working on it at the moment. It's one of the best 1/700 kits I've ever seen.
This is by no means a complete list of good Japanese warship kits, but it's a start. Maybe some other forum members will want to add to it.
Good luck. It's a great hobby.
Youth, talent, hard work, and enthusiasm are no match for old age and treachery.