I've ended up deliberately disbanding veteran units because they make the already easy battles even easier. I really don't need to encourage the creation of even stronger units in my games. That's one of the reasons I don't retrain as it is.

Course with type II governments and gymnasiums, I can't get properly green troops, but I did just raise a fresh army for a deep raid on the Seleukids. There the two chevrons they start with will simply guarantee they can survive to the end of the goal.