I love this guy.
Brugg is one of the many denizens of the Seven-Pillared Hall. He's the face of the non-magical enforcers employed by the Mages of Saruun. He's your typical brutish, aggressive ogre, and players will likely butt heads with him several times over the course of the adventure.
His job is to "keep the peace", "collect protection money", and "act as muscle for the mages". It doesn't require the DM to read far past his Chaotic Evil alignment and his devastating Greatclub attack to know that Brugg isn't going to be buddy-buddy with the players.
In the ordinary course of events, this is the kind of bully players would swat in the opening act as a warm-up to getting down to the real dungeoneering. However, his status as an employee of the Mages puts him in a unique position.
There's no question that the Seven-Pillared Hall only exists by the grace of the Mages of Saruun. It's fear of their power that keeps everyone in line, and lets halflings, tieflings, duergar and drow commingle without murdering each other in the street. If a little rough-and-ready hired help is the price of that peace, it's a price most of the Hall's merchants are willing to pay.
As such, Brugg is a nuisance that players are going to have to put up with. Getting physical with the ogre may well have dire Mage-related consequences, which means that the DM can play Brugg as loud and swelteringly obnoxious as he likes for much of the adventure before the big thug finally gets his comeuppance.
It's good drama. Brugg brings a sense of tension to the Hall, and helps define its rough-cut frontier charm. He's the physical face of the Mages' magical muscle, which (as we'll eventually see) is critical in maintaining the Mages as a real, active presence in the story.
It's also good roleplaying. When players see Brugg threatening their new friend Rendil, they're going to have to resolve the situation without combat. When Brugg demands an "entrance tax" from newcomers, they'll need to pay up or do some fast talking. Brugg is a first step towards reversing Keep's "all combat, all the time" game philosophy, and if he'd been followed up with more of the same, Thunderspire could have been a memorable and compelling adventure.
What Brugg represents, of course, is the rival. He's the perpetual challenge to the players' superiority, a challenge that can't simply be erased by violence. Ideally, there'd be a Brugg in every adventure of every campaign. He's a spur that keeps players striving to be better, in the knowledge that their every mistake lowers them to the level of the peanut gallery.
I think, though, that the best part of Brugg was getting to put the awesome ogre miniature above on the table.