I'd love to see the 'Choose Issue Type' step of the 'Create new issue' process skipped if there is only one issue type. This is mainly for the "create sub task" workflow, but would apply to the "create new issue" workflow.

The default for new installs of JIRA 3.0+ is to have one subtask issue type, 'Sub-Task'. For us, and for most users I suspect, this one issue type is fine. However, it's a minor annoyance to have to click the 'create issue' button on the 'choose issue type' screen when there's only that one type.