jdam explosion:
http://upload.wikimedia.org/wikipedia/commons/5/58/GBU-38_munition_explosions_in_Iraq.jpg
things i notice:
sharp v shaped ejections. the current prong effects do not do justice to the velocity and violence of this ejection. this can only be done with a sprite featuring fine grains on an alpha transparent background.
i think combined with the current effect, with the dark color changed to brown, it would work fairly well.
i honestly think ed underestimates animated sprites. for efficient, non resource intensive dust kickup effects, sprites are still unparalleled. this is because they happen fast enough that the illusion of dimension and volume isn't broken. also, they can be as detailed as the artist cna make them. they can have complex shapes and multiple colors because it's basically an animated texture, something particles require lots of power to do.
some sprite kick up effect from other games as inspiration:
http://pcmedia.gamespy.com/pc/image/article/121/1217397/WoT_2_1327696888.jpg
http://media.pcgamer.com/files/2010/11/Red-Orchestra-2-sandbag-bunker.jpg
what happens is you combine sprite and particle effects to simulate the appearance of dust, dirt, debris moving at different velocity, trajectories and scale.