In the original version of West End Games' Star Wars, the statistics for Stormtroopers were...well...quite pathetic. In game terms, Stormtroopers had 2D in all their attributes and (after armor penalties) combat skills around 3D. I think I understand the reasoning behind this, however. In the movies, we see Stormtroopers consistently missing as they attack Luke, Leia, Han and Chewbacca. So, in order to give that same kind of feel in the game, they made Stormtroopers 'wussy' enough where, on average, they would not pose a real threat to beginning level PCs (who had about 3D in all their attributes and probably a minimum of 4D in all their combat skills). But even knowing the 'logic' behind it, Statistics for Stormtroopers have always bothered me. These guys were, at the very least, supposed to be competent soldiers. And if the 'average' stormtrooper was crap, that made other troopers (like the Rebels on Leia's ship) even MORE crap. It makes more sense to me that the reason why the troopers in the movies couldn't hit the heroes is because the heroes rapidly developed substantially higher dodge skills—especially in Episodes V and VI. Otherwise, you would wonder how Stormtroopers ever accomplish anything—it makes them a joke. It certainly did in my campaign—that is until I revamped the stats closer to something like what you see below:
* This skill is modified negatively by Stormtrooper armor, usually to the tune of -1D. This means that a lot of 'mobility' type skills are hampered in return for a bonus of +1D to Strength to resist damage.
This skill set would represent your standard 'line' Stormtrooper with training and some actual combat experience. Other troopers (especially those who might be veterans of the clone wars) would have substantially higher stats (though these would be rare, considering the attrition the Stormtrooper corps is faced with).
In game terms, this Trooper is a lot tougher—a true challenge to a beginning character, but not an overwhelming one. And even versus higher level folks, a group of these guys, coordinating fire, can be a real threat. Stat-wise, we see that mentally, the average trooper is still equal to the 'average person', while physically, they are much more capable. Considering they are supposedly bred for combat, this makes a lot of sense to me, rather than the 2D average across the board.
This also set a precedent for me for other NPCs. The only ones I restricted to the 2D average attribute thing were generally non-combatants—secretaries, shop-clerks, etc. I figure folks who have been through military training would have above average (2D+ to 3D) physical traits at the very least. In any case, that's just my take and these stats have worked well for me.