Gueuze can include a wide range of flavors. It might be more fun to give no descriptors and see what people come up with.
Flavors you could see can include honey, lemon, orange, cherry pie, mushroom, honeydew, minerality, earthiness, herbal, barnyard, horse blanket, wet dog, leather, almond, sherry, hay and a lot more. The acidity can be fairly low to fairly high--especially for some producers.