Ill answer what i know.
The way you want files stored is achievable. But i dont see a reason to create 5 pools. My file placement rules that have never let me down. I dont have any balancer on and File Placement Rules --> Never Allow files to be placed on any other disks is on.
2- Yes, just unhide or move folders.
11 - Drive Usage limiter should be disabled in my opinion, there is no advantage in your setup
12 - Same Above
13 - Same Above
16- Not necessary i think
17-I think you are right. Leave checked.
18-Duplication space optmizer probably.
20- What you want is possible by default. Balancing > File Placement, look for the TV Show folder and select every disk you want, For the Show 1 folder inside it, select just 1 disk. Be carefull with the except if the drive is full desire, you may end up with the same situation you didnt like, shows across different disks.
21-If Balancing plug-ins respect file placement rules is enabled, rules will come first.
If you are moving with caution you can test most things in a virtual environment with multiple disks. You are overthinking my friend, just set like this:
*Disable all balancers, except StableBit Scanner.
*On File Placement you can leave the main folder(TV Shows i.e) as it is by default (splitted on all pooled disks). In Show 1 enable never Allow files to be placed on any other disks and select the single disk you want it to be stored on.
Now show us a photo of this crazy setup with 50 disks