Aftermarket speakers are always better than factory. They can handle more power. They are designed better with better components too. I put 6 1/2 Orions in my doors and Rockford 3 way 6x9 speakers in the rear deck. The rear is a pain in the ass. Gotta take a lot apart because of the design. Do NOT put new speakers in from the top! Mount them from under.
New radio in these cars is tricky because your info button goes away unless you buy the kit to replace it ($200). I opted for a cheaper alternative by buying a line out converter. My dash hasn’t changed at all, info button is still usable, and steering wheel controls work too. I have a simple stereo in my car. Aftermarket speakers in the front doors and rear deck, line out converter for amp, Pioneer 4 channel amp, and a single 10” sub. I’m going to build a custom enclosure later. Right now I have a simple sealed enclosure that sits right against the seat in the trunk