Thanks for that.One I could mention is Shepherd Seeds. PRG mixed with Lucerne and the other legumes. I think some grass inclusion is important to ensure that at least something grows - esp in the first winter/spring.
I was also thinking the exact same reason for adding grass. I was thinking of maybe Timothy though, as might not cause so many volunteer issues in the following cereals crops. I get ryegrass coming for at least 2-3 years after a grass ley, then have to spend on Axial to get rid of it. Timothy might be better?