"Edenic" would normally imply a state of innocence, which is perhaps not what is meant here. Eden, for Max, is simply paradise - the ultimate happiness.
The bible doesn't record whether the Garden of Eden featured sweet peas.
The Cockney accent originates from the East End of London. One of the best known (but least authentic) examples is the character played by the American actor, Dick Van Dyke in Mary Poppins. Audrey Hepburn did a better job in My Fair Lady.
The crombie overcoat is named after J&J Crombie, the Aberdeen company that first created the three-quarter length wool coat. Today, the name speaks of a tradition of craft and quality which has made the coat an icon.
The 'Big House' was the home of the Anglo-Irish aristocracy who owned much of the land in Ireland. The houses were far grander than the humble cottages of the Irish. Bantry House in County Cork is one such house which has been lovingly restored.