I would recommend talking to the salespeople at Crutchfield to see what they recommend. They are usually very good giving suggestions based on budget and goals and then you can research from there. FWIW, the Audiophiles I know have all of their money spent on their home systems and listen to stock stereos in their car.
I'd rather recommend you Pioneer TS-MR2040. these speakers work great, we installed them under the rear seat on my friends pontoon boat and they sound amazing. we were looking for speakers that would give us the most bass response and play the loudest with the least amount of power. These speakers did not disappoint their 92dB sensitivity and larger size let them play loud and give them surprising bass response even when they are only being powered by a modest 15watt class D amp. the combination lets us park all day listening to music without draining the battery. Look for some reviews on them on cnet.com or topreviews.best to learn more details.
I put in new speakers in my wife's car(Pioneer and Rockport IIRC), and the sound improved. The original speakers were also 14 years old, and I replaced the 12 watt base system with a upgraded 25 watt factory system I pulled at a junk yard though.
If it ain't broke, don't fix it, or you might find yourself investing in more than speakers.
I've replaced the speakers in several of my cars over the years. The ones that I buy again and again are JBL. High sensitivity, and a wide range of frequency response. They're also available in many off the wall OEM sizes so they look stock. Just about any car stereo can power them. I replaced the speakers in my 1981 Buick Regal, and the stock AM/FM radio with analog tuning will thump the floorboards now. It sounds really good.