Your plan for upgrading sounds well planned

!
I can understand wanting to take advantage of your Best Buy discount for your car audio products, however, from their brands, I can really only wholeheartedly recommend two: Rockford Fosgate and Pioneer...
Take a look at the higher end Pioneer source units, of the models listed on their website, I'd take a look at either the DEH-P8500M or DEH-P7600MP for your needs...the deciding factor between these two is whether you want motorization and what your budget will allow...I prefer the aesthetics of the DEH-P7600MP myself...it's just less eye-catching without being too plain looking...and no motorization so less to worry about malfuctioning...
I'd look into the new line of Punch amps from Rockford...without knowing the woofer model and specifications (size, power handling, impedence) it's hard to recommend a specific model amp, but from what you've stated about your musical preferences I's say an amp that will push between 200-300 watts into 1 4-ohm woofer would be sufficient for your setup...something like the RF Punch P2002...it'll get decently loud without being too overbearing and since your enclosure is sealed it will give you volume without sacrificing sound quality...
As for front speakers, I'd recommend cheking out a couple of the local shops, I see you're in Sacramento...I know Paradyme and Auto Radio Stereo both have good reputations, you might be able to find some good front stage speakers at either of those shops (Paradyme has FoCal, Kicker, Alpine and Infinity, Auto Radio Stereo has Boston Acoustics, Eclipse, JL and MB Quart I believe)...Best Buy's offerings are just a bit weak in that department...you'd be better off shopping around to get the most for your money...
Good Luck!
