I haven't been able to try a turtle campaign with the newer versions of MOS, but I've played a slow moving Gondor campaign (focused on retaking only Ithilien before moving into Harad and Mordor with professional armies). I do refrain from building taverns in all but one or two of the starting settlements, I tend to specialize at the beginning of the game. One settlement will produce archers first, one will produce infantry first, etc. I'm not trying to be a jackass, but isn't the only thing that you'll be building by that point the "leftovers" (culture buildings, taverns) after you've upgraded all your towns?