The CC chain you are looking to setup is it restrictive to the target type? Ex: Humanoid, Elemental vs Humanoid, Humanoid, etc?

I ask as you could round robin a CC Focus hotkey and then have another hotkey round robin CC target.

On my setup I have 6 bindings. I'm left handed so these binds are all in my configuration to the right side of the keyboard but something like this could work for you.

"[" = Interrupt Focus
"]" = Interrupt Target
"ALT + [" = CC Focus Humanoid
"ALT + ]" = CC Target Humanoid
"SHIFT + [" = CC Focus Elemental
"SHIFT + ]" = CC Target Elemental

I am updating mine to also include a taunt or some other stuff with "CTRL + [" and "CTRL + ]". This will also include an Action Target Group where anyone who can taunt for example would be in taunt ATG. Anyone who can CC an Elemental say with Banish will be included in that ATG. Anyone who can interrupt will be in the interrupt ATG, etc.

Ingame the keybinds are the same. So in Isboxer I'm just sending the same keystroke to the client that I press on the keyboard. The distinction being with Isboxer overlay it's sending the keystrokes round robin to the appropriate ATG. Because the in game clients per character are configured for their appropriate spellcasts I don't need to do anything really complicated outside of the game.

I personally do not like mouse cursor interactions. It's just not feasible for some of the content where time is short.