Seems there's 3 requirements for any potential aircraft if it is to ever be considered for inclusion into this game.
Doing a search would probably yield this information.
Larry already touched on these. This is why he brought this up:
1) It must be a production craft
No prototypes, no 1-off, no field-modded planes. Must be modeled as it came off the production line
2) It must have served in unit strength
No planes where only 1 flew in a mixed squadron. It has to have been numerous enough to at least fill an entire unit of the same plane.
3) It must have seen action
It must have seen actual combat. No training craft. No unarmed recon craft. No scout planes that were never used. This is why we most likely won't ever get the F8F or the F7F, because neither saw combat. Do-335 prototypes might have done some weapons testing (but records are scarce to say the least) but the production units saw no action at all. They never made it to the pilots.
The Do-335 fails on #1, it fails on #2, and it fails on #3 (not counting prototypes, because they wouldn't be included anyway).
So, if any one of those criteria is not met, you will almost never see that plane included in this game. The plane you suggested meets none of the criteria.
P.S. I've always been a fan of the Pfeil, though. Ungainly, and yet so fast.
