I think the maximum number of policy maps that you can configure is 256 and can apply one input policy map and one output policy map to an interface.Maximum of 32 total classes in an input policy can be configured.Policy names may be of 40 or 64 alphanumeric characters at the maximum.
Hierarchical traffic shaping allows multiple classes of traffic to be shaped at a single rate. A hierarchical traffic shaping policy consists of a child policy that identifies one or more classes of traffic, and a parent policy that shapes the output of the traffic classes into a single shape rate.