The D4Y performed better than the D3A Val but it wasn't as well armored and that became an issue as the war progressed. Of the early in-line engine models, about 900 were built. They then re-engined it with a radial engine, and about 500 were built. The rests were kamikaze variants and IMO shouldn't be counted in a similar fashion as the "normal" versions. It would be a nice addition to the game.
However, Rodbustr, I must point out: There is a reason we don't have many dive bombers in this game, and why they are all early war dive bombers. That reason is that the concept of dive bombing with dive flaps was a pre-war notion and one that was essentially obsolete as the war began. Why have a slow, lumbering plane that put 2 or 3 lives on the line with little chance of survival to deliver a single bomb, when you can risk a single F6F or F4U pilot's life, carry 2, 3, or 4 times the bomb load (per plane!) and get there a fraction of the time. These fighter-bombers also could drop their bombs and defend themselves as needed. It was just a far far better way of waging war, and much more effective. Ju-87s were replaced by Fw190s. SBDs were replaced by Hellcats. That's the way the war progressed, for the most part.
That's why we only have so many -- there were only so many before they were replaced with better ways to drop bombs.