Damn, that Panzerfaust animation is good!

Only comment I would make is that these weapons made a small, but smoky, flash out the front side with even more smoke out the exhaust side. But keep it subtle! Relatively speaking, they made very little flash overall and the warhead was not propelled by the "flash". Users were more afraid of giving away their location because of the smoke and dust.
So, to be 100% accurate the flash should be very short in duration and only visible at the end of the launch tube, it should not follow the warhead. Of course you're artistic preference may decide otherwise!
EDIT: I knew I had a photo somewhere...
This night shot shows the flash at the instant the warhead is fired. Notice how it also travels out the rear of the tube. (You may have guessed I'm a bit of a fan of the Panzerfaust!)