About the Bren... I dunno I think it has one because when you fire it in FH it doesn't have THAT much of a muzzleflash unlike other MGs.
And yes, the spitfire has the correct blades according to the type :)
I'm really looking forward to everything really, but most of all the FW190 and ofcourse the schwimmwagen, and the ME323. And basically everything else really... :D