Clue: New and funny no less, opinion piece is a capital feature (among six others here) (7,6)
Answer: NELSON’S COLUMN
Explanation: Definition: a capital feature (among six others here)
 N(abbrev. for "new") **plus**(and) **anagram of**(funny) NO LESS + COLUMN(a regular article/piece in a newspaper or magazine, giving the opinion of the writer on a particular subject).
Defn: …, that is, features in the capital city of London, hidden in the completed crossword grid.
Landmark 4: