Because I live in western USA with a 10meg connection, I still get average 250ms ping because the server is located in europe....for some it's not our fault.:P
The ping does not make people better at PVP. As a matter of fact, if they have a ping of 500ms, that means overall, they'll react to your actions one full second late, so you have the advantage here. On the other hand, you'll see them move fluently so you can aim correctly always.
If they have a high ping variation (one ping is 100ms, next one 350, other one is 550, and the next one 50) that means they'll jump. The same is applicable if they have high loss. For both things we have limits already, although if I may recommend something, reduce the loss limit to 10%. This happened with about 20% packet loss rate.