One miniature I found a bit disappointing was the Stormtrooper E-Web Engineer. The soft plastic used by Fantasy Flight Games seems less suitable to long, sharp forms such as weapon barrels as it is for organic forms like the Nexu.
The E-Web Engineer’s barrel was particularly wobbly and not at all intimidating.
To get arround this, I dug into my Games Workshop bits-box and retrieved some Eldar guns. Though 40K weapons are mostly too large for Imperial Assault conversions, the slender Eldar-stuff just about works.
So I swapped the barrels of the Engineer with some Eldar-guns.
The result: A beefier, much more intimidating gun. Fire at will!