In the 90s I use to have thousands of dollars of audio equipment in a car that was probably worth around $800 dollars. Good times! I don't remember much, but I doubt any of my knowledge translates much to cars today anyways. Stock systems are so much better now than they were back then and probably much more difficult to swap out with aftermarket components. Although I did just Google Crutchfield, and that's still a thing. And it looks like many of the same names are still relevant: Alpine, Kicker, Rockford Fosgate, JBL, Pioneer.
One thing I would say is to echo what others have said, don't sleep on the amperage. It will improve sound clarity and it's actually easier on your speakers. I wouldn't ignore bass either. I used to listen to a ton of metal when I was younger, and being able to feel the bass when those kick drums are firing is huge IMO. If you build a well rounded system with improved amperage and more balanced treble and bass you may find yourself enjoying the music at lower volumes because you'll have a richer fuller sound that will sound louder at lower volume