The "people with experience" are the ones who say that, like this compression ratio chart at Blower Drive Service:
https://www.blowerdriveservice.com/technical-charts.html.

A GT35 is pretty big, you probably need a tighter A/R to get the boost up. Do you know your compressor diameter in mm?

If I did everything on your $$$$ shopping list, and I got 200 hp, I would shoot a flare into the gas tank.

BTW: I have a fairly stout turbocharged L6, but it's a Toyota.