It's easier for Smiler possibly to be soft-hearted (7)
I believe the answer is:
simpler
'it's easier' is the definition.
(I've seen this in another clue)
'smiler possibly to be soft-hearted' is the wordplay.
I cannot really understand how this works, but
'soft' could be 'p' (musical abbreviation for 'piano', soft) and 'p' is found in the answer.
an anagram of 'smiler' is 'simler' which is present in the remaining letters.
This accounts for all the letters.
This explanation may well be incorrect...
'for' is the link.
Can you help me to learn more?
(Other definitions for simpler that I've seen before include "Easier" , "That wasn't so hard!)" , "Less complicated or complex" , "More easy" .)