Who'd make good sort of theatre publicist? (8)
I believe the answer is:
repairer
'who'd make good' is the definition.
(someone who makes things good again)
'sort of theatre publicist?' is the wordplay.
'sort of theatre' becomes 'rep' (I've seen this before).
'publicist?' becomes 'airer' (someone who airs things or makes them public).
'rep'+'airer'='REPAIRER'
(Other definitions for repairer that I've seen before include "Mender, restorer" , "healer" , "One who makes good damage" , "One having recourse" , "One who mends/fixes" .)