Possible Clues:

• It is so pleasing that the South is not so mountainous
• Makes the cockney girls feel good not to be so plump
• It makes them feel good to have apartments, perhaps
• How it's not those former forte ones that makes one feel better (8)
• Plays to another's vanity
• Less of 18 down on a slope to the South makes one feel good
• Perhaps not such rounders, if one pleases
• Butters up
• It makes them feel good not to sound sharp over the rest of them
• It's more than flat to the South in a complimentary way