Kayin is Korach in terms of wanting honor. Korach felt entitled a) because he was a Kohen, b) he was related to Aharon, and c) both his older and younger brother passed him in terms of getting elected. Korach didn’t care that he was the richest person in the nation, he wanted power. Kayin also couldn’t believe that his younger brother passed him in the Korbanos contest, as well as his brother having 2 twin sisters and he only had one.
Meraglim were leaders/presidents but came back with bad reports because they knew that once they entered EY there would be re-elections and they wouldn’t be in – all politics (Zohar).