Levels of your taijutsu will truthfully depend on you and how much time you put into it .It will also depend on how you see or adapt at seeing what is being demonstrated .
One of your first levels of learning will be to learn to defend yourself and attack back as needed. This will be ongoing refinement till you are way beyond godan level, 5th dan. Once you start to better understand movement and your Kihon you will look at your henka (variation 名詞 )And that will continue to improve through the rest of your life .
Your kihon will need to be looked at observed and refined continously even into your dan ranks. Looking at your balance as well as your ukes ( 週 ).Looking at the physics is a natural science that involves the study of matter and its motion through space and time, along with related concepts such as energy ( 勢力) and force ( 力). Note the kanji used in both are the sword energy and force can be studied as power ,influence and strength. Cause and effect of every movement from yours to how your uke reacts .
Again though you are trying to learn to live and survive an attack being physical or mental. But just keeping to the idea of the physical if you are trying to hard to be in the right spot or angle and not living in the moment the true , you are not alive. Your budo needs to be alive and at your lower stages you need to at least comprehend a true attack. Otherwise you are fooling yourself and leading your students in a dangerous direction. Not being in the fight and moving in perfect lines is a good thing to look at but do not forget the variations of life that will attack each seperate ackground has its own life and dangers.
You need to be able to defend, comprehend the severity of an attack or situation first and through out your training ,this is the budo…
We are as budoka trying to aspire to a grander level but don’t forget the danger and life we teach and train in. The ones that survived the battles are the ones that kept the densho moving forward. When you can do this descently enough then aspire to Sokes movement ( 勢力のない) powerless; with ［having］ no influence.