Yes, I did mention later on, it has to be a software instrument with the default region type set as Pattern which works correctly.
The issue is, when switching to a new template/project, Logic doesn't remember the saved default Pattern. The workaround is to save the entire project itself as a template, which includes the saved default Pattern + software instrument tracks saved with 'Pattern' as the default region type. In other words, the saved default Pattern doesn't seem to work globally across all Logic projects.