I just remember after one of the patches they were nerfed because they no longer got a bonus from the light armor skill, so they became much more vulnerable in melee (mainly with larger groups of enemies).
You just needed to be smarter with picking your prey and be willing to run when things got too " hairy ".

Believe me when I tell you that I was hunting and killing up to 13 NPC's in a single engagement along with dragons llloooonnnngggg before the release of Dawnguard and boost to the werewolf form. I was doing laps around the entire province on a single transformation simply by raiding towns and cities, Whindhelm, Ivarstead,Riverwood,Falkreath,Shorestone are the towns off the top of my head that I turned into ghost towns.

It's all in the perk selection for your character along with the correct standing stone, Alteration can be a werewolves best friend as well as any warrior build where you dump all levels into health&stamina combined with either the Atronach stone or the Lord stone. Sneak carries over into your werewolf, armor spells carry over, and muffle carries over when cast before changing. Some destruction spells carry over as well, Frost cloak and Fire cloak for example, it all boiled down to stopping and thinking things through before you " turn ". And now that werewolves have the perk tree there's nothing that can stand in your way when you act tactically, not even legendary dragons and there's no reason why you couldn't remain a werewolf indefinitely if you chose to I did it.
Sift through the jargen that's in my old thread and you will find a lot of very useful werewolf knowledge, myself and a couple of the regulars tested and what not so I know it's there and I'm pretty sure it was from # 8 on back.
