Dual Wield is my favourite weapon however I think that it is badly designed making it either boring, or annoying to enemies.
The bad:
Steelnado is a skill that puts a lot of pressure on enemies already in trouble, with ZERO effort.
Master DW make Twin Slashes a powerfull apply and forget tool that puts a lot of pressure on enemies. Zero effort.
The lame:
Flurry just like jabs and Uppetcut is an ability that does not work well with how combat is designed. The strong hit of this ability can be easily cancelled by an enemy that creates the slightest distance. It can also be easily blocked.
Imagine a skill like imbue weapons enjoying the passives of DW. Or imagine the first hit of flurry dealing solid dmg and the following hits applying debuffs and or buffs. That would enable a new playstyle.
Whirling Blades needs a bit of damage increase and a bit of a cost reduction. This would make it a solid melee spammable for DW.
Blade Cloak offers defensive mechanisms on a skill line that is supposed to be aggresive.
The best skill of this melee weapon line is a ranged spammable. I find myself relying too much on it since DW has no spammable. I only slot it for maj brut yet here I am playing a pew pew settup.
DW does not have any CC or gap closer. With Clockwork city we have Dual Wielding NPCs that have a very nice looking animation with the above effects. When I think of how overloaded SnB is and how plain DW is my appetite for PvP is leaving me.
Out of all the arena weapons all the effects are weak. Not even one offers ultigen, something that could help both stamina and magika. The only useful weapons, the master DW are OP.
In conclusion DW has some very annoying functions when it offer a more enjoyable playstyle with tools to compliment the stamina builds, who as they currently are, are more or less the same