I don't miss Dual Wield wepon style because I play as a Mage since Origins,so my main weapon is a Staff,but I can feel your pain...
From our perspective,Dragon Age Origins has so many characters options,with many weapon styles and abilities,warriors were master in combat,mastering all weapon trees,rogues are more limited,but yet,they were not limited to daggers...So there was infinity possibilities of characters...
From Bioware perspective,they just think that the classes should feel more unique,without weapon styles crossing between classes...This could make your team feel more unique and you'll require more tatics to choose your abilities and characters...
But in fact,I don't feel so unique...In Origins is where I feel the classes more uniques,in DA II and DGI the only difference between them is the weapon limits and the Rogue's ability to unlock things...
Now it's up to us decide wich limited classe to choose...