There were great bomber destroyers developed that never went into production as they were not needed. My pick?
XP-72 with the four 37mm weapons load.
And for better formation busting, put the proximity fuses from A.A. shells on the High Velocity Aircraft Rocket (HVAR).
Don't count too much on dive speed. Mc200 was suprisingly fast in a dive. "Flight testing of the two MC.200 prototypes was successful, one of them attaining a speed of 500 mph (805 km/h) in a dive, ". I would be supprised by that, but it was fast in a dive.
I'll look through the copy of the...