Mesh system needs upgraded

I currently have a Linksys velop AC2200 it covers great with 3 nodes, but I'm not getting the speeds I would like. I have not researched any wifi stuff in over 6 to 7 years since I bought it. Do the newer ones offer better speed and wall penetration? I have a mother-in-law suit that has a thick wall that needs to be passed through. The velop works but her node always has a low signal. I have 1GB fiber and get about 200-300mbps over wifi. I know many things mess with wifi signal but I don't know if mine can even get close to 1gb speed. Thanks for the help.