Much attracted by one return half spoken about (4,2)

'much attracted' is the definition.
'keen on' can be an answer for 'attracted' (thesaurus). I'm not sure about the 'much' bit.

'one return half spoken about' is the wordplay.
'return' says the letters should be written in reverse.
'half' means to take half the letters.
'about' is an insertion indicator.
'one' reversed gives 'eno'.
'spoken' cut in half is 'ken'.
'eno' inserted inside 'ken' is 'KEEN ON'.

'by' acts as a link.

Can you help me to learn more?