@C0ff33MvYn3 so I still get lag from time to time - but I found out that actually a major issue I was having was due to my laptop overheating. I had no idea what was happening as I'd never gamed much on a laptop before - and this one ought to be more than enough to handle the game. However, getting a cooling pad for it and leaving it with the top up has been a big help. It was so vexing because I had no idea why my performance was dropping and it seemed to be lag, but in reality it was largely hardware related.
That being said - I still occasionally get fairly bad lag once in a while. As for our ps4, I'd just do some regular maintenance things to try to rule out some issues - temps are getting warmer, so make sure its air ducts are clean of dust and it has plenty of circulation space for air. Reboot your router frequently (once a day should be good). You can find your laptop's ISP and set it up for DMZ on your local network (tons of guides for this on google).