For a melee set, Dual Wield lacking a gap closer is the biggest deterrent from its use. Yes, some would say it's got features that help with gap closing, though I see them more as the style of it, 2h is a berserker , 1h+shield is a tough defender, and DW is a high mobility harrier. Contrasting the skills in the line against Invasion or Stampede, it's simply inadequate without supplementing a class skill for gap closing.
Suggestion: Flurry as a gap closer.
I personally hate the skill, I've never liked it, and even posted a video of myself out DPSing it with heavy attacks several months ago. Messing with it again post 1.6 just to reconfirm my animosity towards the skill, I've come to the conclusion what it truly lacks is any valuable utility as a, at best, mediocre DPS tool. But, if Flurry was also a gap closer it would suddenly become a solid build option (especially since it's unimpressive damage was reduced by 8%). Step one would be to change the final attack in the Flurry animation to include a leap/jump/charge character animation which will permit a reasonable distance gap closer (15m-20m). The mechanical changes would be if any of the attacks miss the target, to include the first one, the Flurry animation skips to the final attack animation, which is a gap closer. This makes Flurry "sticky" when used up close, and additionally gives it the utility to be used entirely as a gap closer. Other options for the mechanics of the skill is simply making it alternate based on distance to target, where if the target is at gap closing range it's just the gap closer that just plays the final attack animation, and if they're in melee range it's Flurry with miss = gap close (currently how the Lava Whip free attack alternates the skill from the normal skill to the attack and heal version when detecting an off balance target).
Perhaps it would improve the viability of DW by improving a skill that needs improvement and making the line more attractive for the melee centric play style.
Yeah, I know. If you've been around these forums as long as I have, you've probably seen more than enough of these "DW needs gap closer" threads. My reasoning, "What's the harm in one more?"