I cut my own dampening ring from an old head, too cheap to buy a new head to cut up. The ring lays pretty flat and gives me a really fat, wet sound on my 5.5x14 Slingerland COS as well as my larger and woodier snare drums. I find that it's important to tune the bottom head pretty tight for gigs, particularly if your not mic'd as I'm usually not, or you run the risk of loosing any and all definition to your beat. So I tune bottom medium or a bit tighter, top loose, with muffling ring and/or moon gels.
Also consider stick selection. A light, small head stick like a maple or hickory 5a or 7a doesn't carry much punch. But a 5b or bigger, or I even like the Zildjian laminated 7a (small, round head, but really weighty from the lamination) give a much fatter tone, with light strokes or heavy strokes. This suggestion came from another VDF member a while back.
Good luck,
Brian