I think our gearing strategy at the moment is towards optimizing for tDPS via an EF + ruby mainhand paired with a fast stack stick offhand, in order to take advantage of how tick mechanics work for dual wielding. That type of offhand is usually not so well suited for hota. Additionally, while WW + HotA is a versatile build for farming (I use it myself), HotA and WW are inherently at odds with each other since one is a stationnary attack whereas the other one provides constant movement. For the purpose of ubers, where the bosses are very predictable, I think it's better to go with either a pure WW or pure HotA setup where all the skills are able to contribute in synergy with each other.
As for punish, I'll probably be following build :http://us.battle.net/d3/en/calculator/barbarian#ahRQUP!XZY!bZYZZc
Learning to keep up a high uptime of punish stacks will therefore be a part of my preparation. While non-generator builds can certainly be very potent, I'm not 100% convinced that they're better than juggling punish's 24%. It'll be interesting to see what kind of results our team comes up with using different builds, for all those DW barbs trying to decide on which build to use themselves. Even if it is outperformed, punish is a more accessible build for most barbs so a reference as to how it differs in DPS would be nice.
Tonight when I got hit by Kulle's rocks followed immediately by a pickup by siegebreaker, I tried out Chaz's idea of swapping in a defensive item, though I used a Litany ring instead of a stormshield. It worked pretty well. I think it's worthwhile to pick up a cheap phys res litany ring for a few hundred k, it comes with str(=armour), AR, regen and elite reduction as default so we can swap it in when anticipating an unlucky pickup combo by siegebreaker.