Feel very bump but nothing obviously wrong

My 2015 corolla seems to ride really rough. It's like I can feel every bump and it makes a loud noise when going over bumps. Going over the the centre lane makes a huge bang, and even small drains on the road make a loud noise. There are a few vibrations in the steering wheel at all speeds, even on smooth roads. The tyres have tons of tread and are a supposedly good model of tyre. The mechanic thought perhaps changing all four tyres would help the "road noise" and suggested maybe the internals of the tyres are stuffed. Apparently the suspension and struts are fine. I looked closely at the wheels and noticed one is damaged - not horrific but noticeable from the outside. Should I change the tyres and wheels? Seems like a huge waste with the current tyre tread. Has anyone had a similar issue with bumpiness and been able to diagnose / fix? Cheers. Any help is hugely appreciated.