What type of oats do you find the birds enjoy?
We already use wheat as scratch and to cut the protein content of the feed for the ducks, but otherwise we don't do many treats except what the birds forage. Also the feed is wheat based for easier GMO-free formula without the potential for fraud ... Lots of wheat around here. The birds like it.
The birds haven't seemed to enjoy oats much. I think variety would be good.
Our mill makes a fancy scratch mix, but its price is silly. My breeding partner gets all kinds of great things by the pickup load straight from the field and combines them for her own scratch. If I had the sense she does I'd do the same thing.
Some will turn their nose up to oats. Mine do not, but I have had some that would. Soaking the oats for a few days generally works. Oats has a more complete amino acid profile than the others, and would be by far a better feed if it were not for the hulls.
Hungry birds are not as selective.