I use thin batting or sometimes flannel that has been washed several times. In my table runners, placemats, and mug rugs don't want thickness. Worried about glasses tipping. BUT if you are making them....use what you want for batting. That's what's nice about quilting...some rules CAN be broken or bent.
Lots of us jus like to read posts but dont resond...no idea why. I've posted pic and have had 6,000+ views but only 100 replies.