Not really. I freaking love Busch Gardens Williamsburg and visit 1 or 2 times a year. It's a great park.
But it's not as good as Universal or Disney, sorry. If you're not a roller coaster fan, your options are limited to a single, incomprehensible dark ride, a terrible Soarin' knokoff, or kiddie flat rides. The coasters are great, don't get me wrong. And the food is as well. But it doesn't have well rounded offerings like the big 2.
As for Six Flags, my local one is fine for a day. But it certainly is not more comfortable, and they certainly don't do a better job of keeping the parks clean.