Hi Michael,
I can understand what you mean, but let me try to explain my thinking here. Once again, I will probably be corrected, and then I'll learn something new as well. Like I said, I'm just learning too.
Ok. First training impressions here ...
Turning more into the strike and narrower stance...
... seem to go somehow against advice I got before: that I'm leaning too much into the strikes, and should keep the feet "at either side of a rope". Don't get me wrong ... I know, that this is just a basic rule. Let me put it that way: concerning footwork, I have 3 or 4 major "pillars" that help me at the moment to get it slowly down. Keeping the feet set apart is one of those ... as well as "tearing the ground", and keeping the shin vertical and the knees "on the outside". My feelings are that as long as I need those to get my feet really firm on the ground, I wouldn't try to go "against" one (except one of our Masters strongly advised me to do so) ... even if it offered another advantage.
I didn't actually say "narrow your stance", I don't believe. What I said was to turn your shoulders and hips more into the strike. Take a look at Master Nonymous' Sai video here: (comments afterwards)
The Master is doing a three-phase step, where he goes from a shoulder width stance, brings the feet together, and then out again into a shoulder width stance. This is how we were taught Gunnun Sogi (Walking stance) in Tae Kwon Do.

You'll notice that in that picture the MAist is not leaning forward, which is wrong for our system, but the foot placement is at least similar. The lean is created, I believe, by bracing the back leg and keeping the body in a straight line with the bracing leg,
Now the twist; Master Nonymous twists into the strike, turn his shoulders almost into a line forwards, placing his open side of his body almost completely to the side. The front Shoulder lines up with the front knee also. You can do this by turning your hips just enough without changing your stance, or letting the shoulder pass the knee position. (N.B. I sometimes over-rotate this stance, and am working on that too)
The Cho strike is similar, but in this video (see below) Master Nonymous is doing the Cho to the inside, i.e. towards the front leg instead of away from it.
This strikes me as akin to Tae Kwon Do's Annuro Makgi (Inward moving middle block) where you are blocking across your centre to the same side as your front leg, but with the back hand (essentially). The point is the hip rotation is going in the opposite direction here, and probably requires you to pull up a little on the front foot in order to make the hip rotation work properly.
Your observation on "Tapping the temples"...
... is, in my view, correct. As a consequence, I will stop the "mixing" of the accelerations and will train them in their "pure" form again ... I think I lost my focus here. Thank you.
Shiim ...
... I'm not sure here. I often imagine hitting the limbs when attacking zones 2/3 5/6, so I don't need to go through the middle line. Again, I may be wrong.
I'm sure you would be correct for attacking the extremities, like arms, but if you are attacking the head, then you've got a smaller, more centralised target area to work with, and it never hurts to be able to shiim "to" the centre line, rather than cutting through it as you do in Cho; or WAY through it, as in Sai.
You are however correct about tagging limbs, as in Master Nonymous' video here;
Though I was given advice once to aim more at the centre and follow through a little bit further. I stand by what I suggested, i.e. using a wooden pole as a target. That will give you exactly how far to come through, as you have to touch either side.
And yes, I'm doing all of this in varying "tempi" beginning really slow, and increasing speed to what you see in the vids.
So far up to now...
You doing a fantastic job, and I'm sure you're just going to get better and better, as I hope to do also. I'm simply trying to give you some food for thought; just as watching you practice does me.