I find a lot of peoples builds have no certain ..'goal'. A lot of players are picking up Rapid Fire as a main source of damage. Is this because RF-WF is available early in the game? or do they actually genuinely believe the skill is good?
When designing a build you have to weigh whether you are burst or sustain DPS. Are you mobile or stationary? AoE or Single Target? Being a Jack of all Trades makes you lack in nothing... and more importantly everything. Players need to find a balance towards a certain goal to actually get something out of this so called 'balance'.
Being specialized in PVP might be good, but this isn't really a PVP thread.
Being specialized in PVM makes you weak. Synergy among skills is much more important than being good at just AOE vs single target, or other 'specializations'. Mobility is important, but obviously you don't have to form your entire build around it unless you want to. The concept of 'burst' vs 'sustained' is, I feel, not very useful in this game.
This isn't an MMO; you don't have a tank and healer and DPS. Everyone is dps and control. Having a good AOE ability doesn't prevent you from being good at single target, and having a mobility ability doesn't prevent you from taking RF. You won't get a ton of benefit from dedicating all your abilities to one area, in fact most of them will just interfere with each other. Sure, you may opt to take a one more AOE ability than single target, but you're going to have both. If your group comes against a boss, your group can't afford to have you if you're just AOE. Similarly, your group will be overwhelmed in a big encounter vs hundreds of mobs if you are plinking away at single targets.
I wouldn't think of Strafe as an aoe ability. It attacks targets one at a time, very quickly and randomly. It doesn't do any more damage to multiple targets than it does to a single target. You will probably benefit from having an ability which actually damages several targets at once.
Sharpshooter is thought of as weak because aside from the cool crit at the start of a fight, it doesn't offer much. In an ideal situation against a single target with a slow weapon, it might be good. Say your crit rate is 20% in this situation with a swing timer of 1 sec; you would swing an average of 5 times for a crit, giving you 3% x 5 = 15% crit by the end (an estimate; the real math is more difficult as your crit chance would increase with each shot that didn't crit). A weapon that swings twice as often would get half that. AoE pretty much destroys your chances to have a benefit, dividing that number by the number of targets. So you pretty much end up with 3% crit in most situations. Overall, an ability which increases your crit when you don't crit ends up being somewhat counterproductive.