Sergeant at Arms
I think every infantry class should have access to a shield, especially in siege. I will admit I have been killed a few times being a little too focused on searching corpses for a shield instead of watching for enemies. It is nice having a sword as a sidearm to your bardiche for fighting in tight areas, but without a shield you aren't going to get into the castle.
In Siege maybe, haven't yet played it in BL MP. But overal there are too many shields and they can take too much damage imo.