I hope you dont mean the Ki-84-Ic, when you say ki84. Darn I hated that plane in IL-2 pc version.
The normal Ki-84 would be a nice addition, but the Ki-84-Ic would kind of ruin the gameplay i think.
for the people who dont know the Ki-84-Ic for IL-2 pc: it had 2 20mm cannons, and 2 30mm ho-155 cannons. 1 shot destroyed an aircraft in 70% of the cases, and a bomber in a few shots. But still it was a formidable dogfighter, and had a good speed.
EDIT:
I just saw you've included the B-29. Sure dont hope to see that one in MP
. Would be nice to use it in a training mission though, if they included a kind of mission editor