How to write "Some more prominent figures who have led the protests are ..."
“領導這次抗議活動的傑出知名人物還有：”


還有 implies 'besides' to interpret 'some more';

prominent figures: 傑出(知名)人物; I think putting 知名 here is ok, because prominent figures are often well-known persons. You can remove it based on your considerations. 

who have led the protests: 領導這次抗議活動的