Terminator X Piggyback or not to Piggyback?

Hey all,

I am doing a 408 stroker swap with a TH400 in my 09, bought the car as a roller. The vehicle has no engine harness or ECM, I have a Terminator X that I am going to be running. I am installing motor and trans next week, but my one dilemma is do I piggyback of a stock ECM or just go stand alone, this will be strictly a weekend car if that.

I am not going to run A/C or traction control.

My question is, If I don't Piggyback and run just a Holley, what all am I losing going this route?

Going the Piggyback route, What sensor will I need to piggyback and what is the process of going this route?

If anyone has any information on this I would greatly appreciate any help please and thank you!