Benefit tips
I think the best characters to have benefit are the most essential characters in the game like Abraham, Sebastian, Michonne and all the characters that have crowd control skills. They need to get more buff than others and become more tanky so the can last more on the battle. Second priorities are tanks because they just tanks they don't need more than defense and hp. The least priority for the benefits are Nukers/Dps characters because they will get killed without the essential characters around they will never survive in battle. That is my tips and opinions on this benefit mechanic.