What kind of electronics do you want? The 2SS for the same price as that Mustang GT will include the C&C package, allowing for USB connection, Bluetooth, and aux port. Buttons come on the steering wheel. Even the upgraded Boston Acoustics sound system comes with it.
You can modify all of your other complaints with a little work. The HIDs could run with floods with a few wiring changes. I'm sure a kit will become available for this. In fact, I'm certain that there is a kit somewhere to swap your fog lights with HIDs that could probably be wired to go with your other HIDs. Be creative. Custom parts are the difference between a car and your car.
I'd hate to see you get in the inferior alternative because it is more high-tech inside, but I can't make the decision for you. If that is your choice, we'll be seeing you in our rearview mirrors.
It would be different if you were committed to the Mustang brand, but your loyalty is with GM. Buy what you love and do what you need to make it right for you.