Mostly because cars are less "thick" then they used to be I haven't bought a 6x9 in years. At the risk of sounding like a broken record I usually start with sites like sonicselectronix and crutchfield are
filter for sensitivity over 90db. Its not that <90 sound bad, just that they usually need more power to sound good. Even more than a modern head unit provides. When I do this filter I still get a lot of choices. I usually rule out BOSS, Soundstream, poweracoustik, etc. Even though I like their amps sometimes, not so much with the speakers. Then I sort by price ascending and usually set a limit of around $150 although $100 is what I prefer. I know I'm eliminating some great sounding speakers, but I cant justify the $$. I don't think $200 sound 2X as good as $100. I'm sure someone could prove me wrong. Some brands like Hertz I've never heard. Anyway with the results I use reviews where ever I can find them. I also look for last years model if they are around. More than once I have come back to Infinity Reference, JBL GTO (older), Infinity Kappa (only on sale). You wouldn't go wrong with Kicker, and Pioneer, Kenwood Excelon. I just haven't heard them in forever. If I was buying a better than average pair tomorrow they would be either the older
JBL GTO939 or the
Infinity Ref9633. But admittedly Im biased because Ive had good results.
And related pretty sure I/we (69 fury) can fit these
Infinity Kappa 4x6 plates in the 4X10 dash slot. Face the tweets at each other using a custom adapter. I have a parts 69 dash and the opening is bigger than 4x10 and a custom adapter would allow most of the woofers to show. Then in the corners a set of shallow wide range tweets
like these. These tweets go down to 400 hz so you get highs and midrange. Hoping to get some stereo effect back. All 4 powered by a similar amp to what I suggested earlier. Then another, maybe same amp, to power shallow midrange in the kicks (I already have holes - I did not do it!) and 6x9 in the rear armrest. Again the PO put holes in those valuable things. And then sub. Maybe 2 10s behind seat, or shallow under seat. Not sure if its shallow enough. As soon as I figure it out I find a new brand or idea. But its all fun. I figure since I look at this stuff I might as well pass it on.