The character of the particular herb should be distinctive in its aroma. Overall the aroma should be a balanced combination of malt, hops and the featured herb as appropriate to the specific type of beer being presented. If the base beer is an ale then general fruitiness and other fermentation byproducts such as diacetyl may be present as appropriate for the warmer fermentation.
If the base beer is a lager, then overall less fermentation byproducts would be appropriate. Some malt aroma is preferable, especially in dark styles; hop aroma is absent or balanced with the herbs used, depending on style. The overall aroma should be balanced and harmonious.
Appearance should be appropriate to the base beer being presented and will vary depending on the base beer. For lighter beers with spices that exhibit distinctive colors, the colors should be noticeable.
The character of the particular herb should be distinctive in the flavor profile. Hop bitterness, flavor, malt flavors, alcohol content, and fermentation byproducts, such as diacetyl, should be appropriate to the base beer and harmonious and balanced with the distinctive herb flavors present.
Mouthfeel may vary depending on the base beer selected and as appropriate to that base beer. Body and carbonation levels should be appropriate to the base beer style being presented.
Overall balance is the key to presenting a well-made herb beer. The herb should complement the original style and not overwhelm it. The brewer should recognize that some combinations of base beer styles and herbs work well together while others do not make for harmonious combinations.
