Not a Kawasaki. It did look somewhat like the Hien, but then so did several other aircraft of that era. Here's today's clue and your bonus clue.
Looking for the name of a warbird.
1. Designed and built early in a war. It was an improved version of an earlier airplane from the same manufacturer.
2. Its performance in one role was acceptable, but that role was not one that its country had much need for at the time, so it was given other roles, for which it was ill-suited.
3. It was flown by three services of the one country that used it.
4. It was a fighter. It was considered hard to fly, although one of its country's top-scoring aces got some of his kills while flying it.
5. One reason for its poor handling was that it had a higher wing loading than many of its contemporaries.
6. Another problem, at least initially, was that when it first went into service the pilots who flew it had previously flown airplanes that were much more docile.
7, Despite its shortcomings, it was probably one of its country's best fighters when hostilities began.
8. It was faster, at least at high altitude, and had longer range than the enemy fighters it faced.
9. Most of them were armed with machine guns, in varying configurations. A handful had cannons, and some had rockets.
10. A few thousand were produced.
11. Production pretty much stopped after about one year, mostly because the engine manufacturer (or possibly manufacturers) shifted to production of a similar engine for a different airplane.
12. Although it was fast, its rate of climb was inferior to that of the fighters it opposed, in part, perhaps, because it was heavier than the airplane it was designed to be an improvement of.
13. Over the course of the war, in which it served until the end, nearly half of them were shot down.
14. It was designed to be a high-altitude interceptor, but it found itself in a situation where that kind of airplane was not of much use.
15. The thing that makes clue 3 puzzling is this: The country for which this airplane flew had an unusual, perhaps even unique, way of dividing its armed forces into services.
16. Some of them were used for ground attack, sometimes with machine guns in under-wing pods to increase their fire power. They were not particularly effective.
17. While judgments about looks are subjective, it seems safe to say that this was an attractive airplane. It has been the subject of RC modeling, including at least one ARF, plastic models, and a rubber-powered free-flight kit. It is a well-known airplane.
18. It was powered by a liquid-cooled V12 engine.
19. It looked a lot like the airplane it was designed as an improvement on.
20. A version with a radial engine was tried, but it was a failure and never went into production.
21. It was a streamlined, low-wing. single-engine monoplane.
22. The factories that built it also built one of its country's best known planes. That airplane used the engine referred to in clue 11, and the factories increased production of that airplane when production of our target airplane stopped. These two airplanes were designed by different concerns.
23. When it was first used in combat, its gunsight was inferior to those used by enemy fighters.