I remember when I filmed my documentary I had about 35 questions. It made people seriously stop & think outside the box. There were a couple of times some asked for me to stop rolling due to being stumped
The questions were written to get the best out of the person being interviewed. Like what Mr. G stated earlier in this thread.
Funny thing is, you place a camera in front of a rapper & he becomes an instant infomercial. He becomes the greatest pitchman since Billy Mays. If you can calm them down & humble them and get past that & get them on film? You'll have some great interviews.
Also, keep in mind. Some people seriously don't know how to do interviews. You may have to stick around a little longer and ask the same questions two or three times to get the best out of them when they finally relax & get comfortable in front of the camera.
I'm looking forward to seeing some great work from you, Bro. Seriously.