The drums will sound better and only mass absorbs sound. The whole platform should be floated of neopreme doughnuts. Now I mentioned neopreme doughnuts before. Doughnuts, you get them at a acoustical building supply centers. The kind with two holes in them.
Bottle stoppers are also cheaper.
A word on carpeting. Carpet will not stop sound from vibrating your neighbors. Carpeting only deadens high frequency sounds from resounding off the internal walls of your sound room. A room with all carpet on the floors walls and ceiling makes my ears ring. Same thing with sonex on the walls or egg crates or acoustic tile.