Well the verdict is still out on casters as they get to 20 but I have seen some spells work well in shavarath for instance irresistable dance and web and also flesh to stone is excellent in a variety of situations. I am really interested to see the topflight wizards in action because they now have the highest dcs as they try to figure out what spells work, their feat selection, and how to cast the spells. In the raid debuffs also are very nice especially on parts 1 and 3.