In other games, I've had instances where players don't want to rock the boat to voice something they don't like or are afraid to raise concerns about the dwindling levels of punch and pie in the games. Well rock away, cause I've set up an anonymous Suggestion Box where you can voice anything you'd like. Hey, even complain about the box if you want. You don't have to give any details about yourself, and can leave it generic like "The campaign I'm in hasn't had one cute animal cross my path."

https://www.surveymonkey.com/r/DH2TQQG

(And, yes, I know I left this as Group 0. So now even those without a voice in my games can now have a voice.)