Interesting and critical work!
I don’t think there’s enough info about the amount, context, and rest of your work to understand at what level you should be starting these: single task, pair of tasks, something higher level.
I disagree with @Bastien_Siebman’s “try avoiding subtasks all together” recommendation. Although subtasks can cause problems if not used properly, this is too strong a caveat and is throwing the baby out with the bathwater.
Both issues above are addressed in my free eBook chapter in Bastien’s book:
I think you’d benefit by taking a look, because it will help you wrestle with the pros and cons of different solutions and allow you to arrive at the best decision for your use case because you know the details much better than we do.
Hope that helps,
Larry