Dude, be happy with those numbers, learn the car, and when you are ready to, turn up the wick.
450rwhp and 500ft-lbs PEAK doesn't mean anything, so don't get discouraged by that! I've dyno'd cars that make 90% peak power over less than 5% of their rev range, and while they can say they've made XXX horsepower at the wheels, I can also show them 5 or 6 other cars with significantly less horsepower that would absolutely slaughter them in any kind of race. Peak horsepower numbers sell cars... and are used for bragging rights on the internet! Power delivery is much, much more important in building a fast car.
Post up the graphs if you have them, they tell the tale much more accurately. I suspect with your setup you are going to have gobs of torque everywhere, and a nice fat power curve. That's what I'd be happy about.