Want smoother quieter ride

If this question has been asked and answered, please let me know where or how I can search for it. Tried a few searches, but couldn't find much.

I have a 2001 Mustang, all stock as far as I know. Compared to other cars I've driven, this one is louder and bumpy. I would like to reduce road noise and have a smoother ride. I don't care much about performance since this car is mostly used for long distances on the highway. Comfort is higher priority.

For the road noise, I know I can install dynamat or something similar. What else has the most effect?

certain kind of tires? (I have the standard 15" rims/tires)
do new shocks/struts help much? if so, what brands are recommended?
springs?
anything else?

Thanks,
Mike