My team has found that one of the ways to easily sort the hierarchy of tasks is to use a Custom Form with "Task Types" that relate commonly to Agile types: Epic, Story, Task, Sub-Task. We also use "Bug".
Some companies may want to add custom options like "Event" "Campaign" etc similar to "Bug".
Having this as a default (with customization much like Status) would be much more user-friendly than an embedded Custom Form.
A secondary request would be to have icons or colors associated with these.