>I dig the WRX, but I would love if the engine were quieter.
As far as the WRX goes I would say you're in the minority. There was quite an uproar when Subaru ditched the unequal length headers on the WRX, eliminating the famous boxer rumble. That unique exhaust note is one of the reasons people love the WRX.
>IMO a quieter engine is always desirable - akin to how I always want my computers to have quieter fans for any given level of performance.
Aftermarket exhaust systems are quite popular, but I can't say that I've ever seen a computer fan noise amplification system. I understand not everyone wants a loud car, but there are plenty of cars coming out with factory valved exhaust so you can make the car scream when appropriate, and not just on high end sports cars either.