This is a great discussion, and thanks for the fantastic post, John!
I have a client who has a 3.4.1 multisite install with custom users roles. She wants certain of her users, who aren’t admins, to be able to (Condition 1) moderate their new bbPress forums – 2.1.3. But, she doesn’t want them to even be able to (Condition 2) even see the other plugins in the Dashboard. I’m concerned about using manage_options because I don’t know whether it would fulfill condition #1. What is the best way to set this up?