Tornado and freeze, you spend 3 or 4 elixer and cannot take out spear goblins is a major problem. These spells should be more appealing to be used regularly as main spells (not just arrows and log and others). Freeze has only 4% usage in ultimate champion it is the lowest of all the actual spells like zap, arrows, etc (not talking about the spells that spawn a troop).
Royal chef has the lowest usage rate at 5%. He is good (almost only in one deck) if you keep the offensive pressure. But on defense he is really bad with that slow hitspeed nerf. Maybe the quicker cook speed buff (when one chef tower is remaining) will help.