1)
Why did he say "ha'Chefetz la'Shem"?
1.
Malbim: Chafetz is something that one's soul intrinsically desires. Ratzon is based on thought - one desires it due to its attributes. Hashem does not intrinsically desire Korbanos, only because His will was fulfilled. That is Chefetz Hashem (what He intrinsically desires), heeding His word!
2)
What is "Shemo'a"?
1.
Rashi: It is heeding Hashem's word. It is better than Korbanos.
3)
What does the end of the verse teach?
1.
Rashi: Hearkening to Hashem's word is better than Chelev of rams. Malbim - Hakshavah (hearkening) is a lower level than Shemi'ah (heeding), and still it is better than the part of the Korban that is burned to Hashem!