I don't see this aircraft mentioned often when people put up lists of the Japanese aircraft they want, probably because it is more noted as a reconnaissance plane than an interceptor. But the Ki.46-III-Kai version carried 2 nose-mounted 20mm Ho-5 and a single, upward firing 37mm cannon. This speedy twin-engine aircraft exceeded 390 mph (nearly as fast as the Ki-84) and appeared in combat during late 1944. Over 600 III models were completed - not a ton, but significant by Japanese production standards.
I wonder how well the upward firing cannon would work in AH? Would the gunnery solution be too difficult to get, or would the required position underneath the target a/c leave your plane too vulnerable to defensive fire? Plenty of Axis twin-engined interceptors used this design, and I've always been curious how it would work in a sim.
One thing about the B-29: I think it would be a great addition to AH, because the alot of the community here wants the biggest and the best at everything. But is it too big to spawn from the current bomber hangar? How much clearance does the B-17 have when rolling out of the hangar? The B-29 might not fit...