Just checking back in to say what a difference a month (or two) makes! Another few weeks in the keg (as Butch suggested), and Northern Brewer's Brunch Stout kit took on a smoother, deeper, more flavorful persona, with a thicker, creamier head and that appearance at the pour that I describe as "fallout," in which the bottom of the head appears to settle toward the bottom of the glass. (You seen this before if you've ever seen pint of Guinness fresh from the tap; sorry for the lame description.)
Karl came over with his counter-pressure bottle filler to help me fill some canister-top brown bottles for a family function in Wisconsin -- my uncle was celebrating his 70th birthday and 30th anniversary, and requested that I bring beer. I didn't want to bring the keg, partly for logistical reasons, and partly because this is not a beer for everyone and not a beer for a binge. (It would've broken my heart to see half-consumed plastic cups of brunch stout warming in the morning son after the celebration.) The bottles went over very well, however: Uncle Mel enjoyed it; Aunt Sandy turned green; my dad, my cousin's husband, and a local microbrew enthusiast all loved it. All good signs.
I recommend the kit whole-heartedly now, only give it time to mature. I'd love to taste it six months from now, but I'm afraid this keg is almost kicked. Cheers!