A twincharger system (supercharger + turbo) sounds awesome in theory, but good luck implementing it well and getting all the transitions to happen smoothly for a good daily driver without more than doubling the cost of the vehicle. That kind of stuff requires good electronic control over the clutch, bypass valve, and wastegate, integrated with the rest of the engine control systems. No one makes such a kit, so it would be a totally custom system.

A sequential twin turbo setup is more realistic than twincharging, but even that would be very expensive as a one-off custom system and may suffer from some daily driving compromises with purely vacuum/spring controlled valves, etc.

It doesn't seem worthwhile to discuss theoretically optimal setups that are vastly different than what is available on the market, unless you have the money/skills necessary and plan on building and tuning a custom system.