I feel that it's not a matter of how you use the character, just the character itself.
No, that's wrong. That's literally how contract are made for characters, IT IS the "how you use the characters" not just "The characters itself"
cf:
-Mickey being used in only one Scene in KH I and only having a contract for ONE scene and Nomura literally decided to make the story about that ONLY scene in the contract of "let's find the king" and making him appears at the end.
- All of the characters contract in Wreck it Ralph where each company specifically tried to make sure HOW Disney had to use their characters
- Sonic being allowed to be ONLY shade of blue in Smash, alongside Pac-man only being Yellow
- All of the Roger-Rabbit deal wich was a cluster**** and Disney/Warner making sure each of their characters had the SAME screentime/Lines
-Leaked contract for Pokemon merchandising explaining exactly that it's HOW YOU USE the character that is important depending on your licences
etc...etc...etc...
the list is long, but there tons of others exemples.