I think it is ok to set out more actions then one in a project plan or in omnifocus.

However, I think it is key that you are able to "let go" of a next action that comes up if it doesn't quite make sense anymore. Something you have learned along the way may make a next-next action not really apply or be attractive. In the weekly review, you need to be fairly ruthless on evaluating the next step that comes up.

Randy