Mixed decoy spread question
We are hunting on the TN river. I have hunted there for 5 years and have only used Mallards and black duck decoys. With a dozen Bluebills. This year we purchased a dozen gadwalls, dozen pintails, and a dozen buffleheads. Along with the 5 dozen mallard and black duck and dozen bluebill decoys we already have. The question is would you just mix all these decoys together or would you put them into groups within the spread. Or what would be the best way to set or mix this spread up. Thanks for any advice in advance.