Well they only made 2461 CTS V's in 2004, which was the first year of production and it holds the title of being the fastest 4 door sedan in the world at the time. While that may be impressive it's not a garage queen so monetary value just isn't a factor.
I truly do enjoy driving it though but I know if I want to add power, as you stated, the balance will be askew. If it was a 70 Chevelle the answer would be much easier.
When we were teenagers it was nothing to do an engine swap. Putting a big block where a small block Chevy used to live was simple. Money was tight back then so we cut corners and did practically everything ourselves anyway.
But with these newer LS engines and anything with fuel injection you certainly have to know computers. Heck, even the trucks I drive now are controlled by computers. And they have to interface with the mandatory electronic log in device (ELD) to be DOT compliant.
Jeff Hagaman built a CTS V that was making over 1700 hp using a 427 LS block with twin turbos (I'm wondering how much hp you can get out of yours Rich!) and it held records for rolling 1/2 mile, standing 1/4 mile and top end but he had to back half the car with a pretty tricky 4 link. The car still had OnStar, power windows and a back seat! I don't have that kind of money though. Incidentally, Jeff got killed trying to set a record in 1/2 mile in his Nissan GT-R at over 200 mph in New Orleans.
https://video.search.yahoo.com/searc...5&action=click