Another option would be not to use dependencies, but to create the next task once the previous is complete.
I can’t speak for Asana, but I don’t think chances are good for your reqest to be implemented, with the existing options with dependencies and rules.
That said, I do agree that creating/manipulating dependencies in templates are a hassle, for that this request might be relevant: Make live projects, project templates, and my tasks variations of the same class
Probably also slim chances of getting implemented, but who knows. 