If you absolutely want to use light armor, that is your choice, and it does give you some Stamina perks, but IMO you should go with heavy armor for a DW build. My main reason for saying this is because you can't block when DW, meaning your armor is going to have to soak up the damage. Light Armor does not do this nearly as well early on in the game. Now, once you increase smithing skill and light armor skill, you will not be at such a disadvantage. I realize that the point of DW is crazy damage output and you intend to kill things faster than you kill them, but in the early part of the game it is difficult to do a lot of damage even with dual wielding. I am speaking from experience as I did a DW, light armor, sneak build. I did fine until about level 12. Sneaking and doing stealth kills in dungeons is still easy, but in the open I die often, since I rarely can sneak up on Sabre Cats and Bandits now, and they do more damage than I do at this point even with DW. Case in point, when going up to
I was 1 hit by a Sabre Cat. Even with a sneak bow attack, poisoned DW strikes, stagger with shout, DW strikes, stagger with DW power attack pattern, the Sabre Cat ended up killing me and I only took about half of his health off. Long story short, I recommend Heavy Armor for a DW build and
Spoiler in case you are curious, I believe the strategy guide recommends Heavy armor as well for a DW build.