after a while, when your empire gets somewhat bigger, and you have lots of generals running around, you eventually stop caring about ancillaries. They arent worth the bother, trust me. I played the Scipii and my generals were always separated by many long leagues, so its just a waste of your generals moving them around just to exchange ancillaries. They are of much more use near the front and there they stay till old age claims them. I might mourn the occasional passing of a super general with some nice retinue members but i forget it soon after. Many more where those came from.