Though not wise, the message may merit discussion (6)
I believe the answer is:
themes
'though not wise the message may merit discussion' is the definition.
I can't judge whether this definition defines the answer.
'though not wise the message' is the wordplay.
'though not' suggests deleting specific letters.
'wise' becomes 'sage' ('sage' can be similar in meaning to 'wise').
'the'+'message'='themessage'
'themessage' with 'sage' taken away is 'THEMES'.
Can you help me to learn more?
(Other definitions for themes that I've seen before include "Subjects or repeated melodies" , "Recurrent ideas" , "Motifs, subjects" , "Subject matters, motifs" , "Subjects or unifying ideas" .)