Yes, he'll make a poet! (7)
I believe the answer is:
shelley
'a poet' is the definition.
(Percy Bysshe Shelley 1792-1822)
'yes he'll make' is the wordplay.
'make' indicates an anagram.
'yes'+'hell'='yeshell'
'yeshell' with letters rearranged gives 'SHELLEY'.
(Other definitions for shelley that I've seen before include "Ode to the West Wind poet" , "Percy Bysshe . . . . . . ., great English poet" , "Mary - - (Gothick writer)" , "English Romantic poet" , "Author of Frankenstein" .)