Indeed it will be expensive, but honestly, if you want to supercharge your K24, do it. I think if you're looking to build a racing car the Accord isn't what you need to start with and perhaps that's what some of the guys above are getting at, but just the idea of supercharging an Accord Exec or Type-S could be a lot of fun. Yes you can buy a different car with greater performance for the money, but that's not what it's all about for some folk. Sometimes it's the pursuit, not the arrest if you catch my drift. More satisfying to do something mad with your car as opposed to just buying a faster one.
If I had the money, I'd still keep the Accord and do all sorts of crazy things with it, because I love it. I know it will never out-perform lots of cars, and I'm comfortable with that. Doesn't mean I want these other cars. Certain cars can have a soul that earn them a special place in your heart. It might seem crazy or illogical, but for some people, it makes more sense to spend the value of a new car on the car you have be it to keep it running, or to improve it's performance to your taste. Different strokes for different folks, horses for courses and so on.