Dormer I think displays good qualities (5)
I believe the answer is:
merit
'good qualities' is the definition.
(merit means good quality or worth)
'dormer i think displays' is the wordplay.
'displays' indicates a hidden word.
'MERIT' is hidden in the letters of 'dormer i think'.
(Other definitions for merit that I've seen before include "Rate" , "Worth; deserve" , "The M in OM" , "of a high order?" , "Quality deserving reward" .)