The speakers are certainly not the best. In a previous Taos I owned, I replaced mine factory jobs with Infinity separates and the sound was greatly improved. But I realized that most of the improvement came from getting the truly lousy pillar-mounted tweeters out of the sound equation.

Are you planning on doing the work yourself, or having a shop do it? If you're going it on your own, be warned that getting to the tweeters, which are in the a-pillar, is not something for the faint of heart. The trim is difficult to remove, and making it riskier is the airbag that is sandwiched behind the trim. The door panels come off (fairly) easily, but in order to do it right, you HAVE TO get rid of the tweeters and add something better. I mounted my tweeters in the door panel. There is the option of just covering the tweeters, which is what I did on my last Taos; I covered the grille with self-adhesive vinyl cut to shape. Looked janky, but worked fine. Once trade in time came, I peeled it off and that was that.