I made it through part of your post.
Here is are several takes you may not have considered.
1) You seem to be trying to do everything and every contingency with a "lesser" rig.
2) It is, even by your own admission, not the perfect rig.
3) You're going to spend a tremendous amount of time and money on this thing.
4) If you do manage to get all of this done you'll almost certainly overload some of the components of gimbal and top stage and post and arm and vest and something bad will happen!
5) So, my take, why not do half of what you are planning, spend half as much time and money and then use the rig within its weight and purpose built range then move up to a more "purpose built" rig?
6) You're trying to do what we all want to do, make a cheaper rig do more than it should and be able to charge more for your services without investing in the gear. No fault of yours we all want to doo that. Investing is good; you get tax breaks and you end up with good/perfect gear for the job (not homemade stuff) and you get to charge a lot more with much better paydays!
I wish you good luck and maybe someone can help you with the wiring.