I used this, obviously swapping out/in runes as I got the level for them for normal+nm.. Could easily swap Battle Rage for Furious Charge w/ Merciless Assault if you want a little more mobility and a escape..Stomp a mob to stun and bunch them up a little -> Whirlwind and Cleave to finish them off (using revenge whenever it's up also).. Bosses could swap out Cleave for Frenzy w/ Sidearm and Charge for Wrath (just for more ST dps)..
It's when you get on Hell imo that builds become more eh.. required? I guess.. I was just using whatever for the most part and did fine throughout N+NM, before settling on that build in act3 NM. That said despite Barb being my first I main WD so i'm not the best to go to for Barb advice, i'm sure others will chip in also.
tl;dr Use w/e until Hell since Barb just rolls face across 1/2/3/4 whilst spamming mouse and watches everything melt.. Defense doesn't play as huge a role in N/NM as it does Hell and especially Inferno..