Thanks for responding, it helps me associate you with selected paths and approaches. What you are describing in your first post is much the same approach taken in my training back in the early 70's when I started and they are good tools. The idea of not contending over the point of conflict, here the grabbed wrist, is basic and central, though seeming very hard to learn and retain.
An addition to the wrist grab exercises you are describing above that you might try flexing your wrist and forearm prior to them grabbing you tightly...so both of you are tense. Repeat this a couple of times. On the next round once they have a tight grip relax your wrist and forearm and check the response and reaction of the person grabbing as well as yours....what does your elbow do or how does it move and from how does your should react? You can then follow this by relaxing all the way back to your center and from your center outward to the ground. Releasing your wrist (as the nage), releasing the elbow, the shoulder and so on. It is relax, relax again, relax again.........and relax again. This of course leads to releasing before you get grabbed.
To me this is the start of practice that leads to all the other things you want to do with your Aikido. Relaxing is one the elements of arriving at an active spirit, active intent, active mind, fluid one body that leads to the levels of blending, leading and harmony that is your approach to Aikido.
Just a comment about Tohei Sensei. There was a connection between our instructor and Tohei Sensei from the 50's in Hawaii so back in the 70's he was in our dojo several times teaching an evening class...maybe 25 individuals on the mat. It was a regular Wednesday night advanced class. Tohei Sensei's techniques were fast, precise, and right on. I could feel the potential power and knew I had to get out the the way. He was also hard as a rock wall and grabbing his wrist was like hanging on to a 4" diameter pipe you could not stop from moving in any direction he wanted.
keep having fun