Rule reminder
Stylistic choices: 'sebbene' is the most common formal choice; 'benché' is slightly more literary; 'quantunque' is archaic/very formal; 'nonostante' + noun is concise and journalistic; 'pur' + gerundio is elegant and avoids a subjunctive clause.
«Il dibattito parlamentare è stato acceso, _____ i temi trattati fossero già stati discussi in precedenza.» (parliamentary column)