I think they are unnecessary and the game looks better without them.
I brought up the idea before release but Madmat shot me down, so I finally downloaded the modding suite and had a go myself.
MRLS and other rockets still have smoke trails.
Muzzle flash and sound effects have been left untouched.
Note: being hit with arty is now more scary for you and your opponent!
Using this mod you will just hear the "whoosh" before the impacts devastate their targets.
No more following back the trails to betray the position of enemy guns...
No more studying the trajectory of the trails and moving your units before they are hit...
Download here: http://www.filedropper.com/ndfwin
Install instructions for those new to WRD modding:
Replace the NDF_Win.dat file found in the location below with the one you have just downloaded.
C:\Program Files (x86)\Steam\steamapps\common\Wargame Red Dragon\Data\WARGAME\PC\430000366
Launch the game as normal. Keep a copy of the original file and simply copy it over the mod version to get rid of the mod if you do not like it.