We have the basic, i.e. bottom of the line, AM/FM/CD/ Stereo unit in our 2010 RAV 4. I replaced/upgraded all of the large speakers, front and rear, but not the tweeters. There was a noticeable improvement in sound quality. Now that the CD player is not working, I thought maybe replace the defective unit with the best upgrade, i.e. better sound quality. However, I would want it to still be factory look and fit, and utilize the same wiring harnesses, plug-ins, etc. for an easy switch. Any recommendations and what year model range would work? Thanks for your suggestions. Also, minimum requirements would still be AM/FM/CD player.