In fact, one of the technological innovations that 3rd Reich scientists developed was the modern day assault rifle. In fact, the Nazi design was so effective it is still
around today; the AK-47. Oh it's been tweaked and modified a bit, especially the newer models, but for all intents and purposes it's the same weapon the Nazi's had. If they'd been able to develop and mass produce an assault rifle like that, the impressive firepower advantage the Nazi's enjoyed for the bulk of the conflict would have been even more overpowering. It might not have been a deciding factor in the war, but then one can never tell.
As for the rocket packs, I'm stuck thinking of that little Nazi propaganda flick from "The Rocketeer", with the thousands of 3rd Reich RocketTroopers soaring over the Capitol and whatnot. Of course, in BF1942 it's going to be a lot cooler since you can plink them out of the sky. Wonder if you'll be able to have a jetpack instead of a parachute?