Average entry length should be at least 5.5. The Listener Crossword website gives instructions and guidance to setters on such matters.
Ok, the clues were on the easy side, but the grid was a masterpiece of construction, with one of its best features not mentioned in the preamble: the endgame, replacing a surprising statement with a name, results in an astounding number of new real words. Any setter who has attempted such an endgame knows what a feat that is. Chapeau to Remus!