Does this get rid of the rubber-banding?
My performance is fine - never freezes or stutters. But the player lag is just obscene. Players rubber-band and warp all over the place. I feel like I'm online gaming circa 1999.
When people talk about "lag" they mean the action on screen is behind the action you are performing with your controls. This can be caused on the client (your pc) by it not being able to keep up. That is what the suggestions above do - reduce the load on the client. CPU, graphics card, memory and so on.
Other lag is caused by latency and the consistency of your internet connection. Latency is time it takes for a message to travel between the client and server. This is your ping. A high ping means a constant delay. 100 ping is 100 ms which means 1/10 of a second delay to the server. Under 100 is usually barely noticable. Over 250 is like old school dial up latency.
You can also have drop outs on your connection where you get nothing for a few seconds. This can be caused by issues at the internet connection on the server, on your end, in between, or someone on your local network using all the bandwidth downloading a movie or something. It can also be caused by the server freezing or being busy.
Rubber banding is generally caused by the game running on your client losing connection with the server for a moment. Rather than freeze, it keeps going and tries to get back on track. Often it cannot and it rewinds you back to the last position the server has you at.
So the above will probably not help your rubber banding. A better internet connection might, but the problem might also be out of your control.