Even missed attacks build Rage, so missing your opponent isn't really a huge issue
The way most of your fights will probably go is, throw your quick, endurance saving attacks until your Rage is built up to a decent level. You're going to take some punishment here, but that's alright.
Once the bar is built, switch to your heavier attacks and you should be taking down everything around you in one or two hits. You're not going to take much more damage, because at this point the fight should be over in a matter of seconds.
If you're still in decent shape, pop your healing power or a green pill and rush headlong into the next mob, because your Rage will diminish quickly. If you get to them with a decent amount of Rage left, you should be able to take them all out quickly and not take much damage in the process.
Repeat until your health begins to look dire. Then rest and repeat.
Brutes are interesting because they make extensive use of both Brawl and Rest, which if I'm not mistaken, most players tend to remove from their tray at the earliest opportunity. Rest and Brawl are integral. Use them.
