1. Synonyms for Commonplaceness include sterileness, flatness, blandness, dreariness, vapidity, drabness, flavorlessness, insipidness, lifelessness and staleness

2. Antonyms for Briskness include inactivity, lifelessness, lethargy, laziness, idleness, indifference, apathy, dullness, indolence and carelessness

3. Antonyms for Astringencies include blandness, weaknesses, plainness, mildness, banality, triteness, tastelessnesses, insipidness, jejuneness and lifelessness

4. 24 I thought it an apt and correct description, with its connotations of inertia and lifelessness.

5. There are many synonyms of Blandness which include Drabness, Dreariness, Flatness, Innocuousness, Insipidity, Insipidness, Lifelessness, Pallidness, Vapidity, Jejuneness, Vapidness, Colorlessness, Boringness, etc.