I don't think the OP is trying to reduce road buzz. Knowing the source (BQ) and the low-trail design, I'm guessing this is going on either an older sport-touring type bike with a high-rake (offset) fork as was common for the day, or a modern repro model of similar design. They typically handle better with a low center-of-gravity front load due to the geometry of the front end. The issue becomes one of flexibility from the large degree of bend in the fork, and attaching a rack is a means of trying to stiffen up that design. Especially if using a wider tire like the 32 - 35 the OP mentioned, road chatter won't be an issue.