Usually when I find a better bite with a larger jig body it's because the larger body is allowing the jig to fall just a little slower. Depending on water depth the fish are sitting in I may try using the smaller bodies with a lighter jig like a 1/32 oz. Where and how crappie bite seems to be an ever changing symptom.
3 weeks ago (here in Ohio)I caught everything on a 1/32oz jig & now the 1/16oz seems to be the ticket. Depth is all over the place from 1' -12' deep in 2-35 fow.