I just changed cable companies.

New speed is supposed to be 30 Mbps.

Getting 27 or so at direct network connection.

19.50. Up and 16.30 down on my wifi.

Cable guy says I should get the same as network connection but their service doesn,t work well with dlink routers.

Just bought router last month so I know it is up to date.
Could there be a difference in router performance?

Depends on what you have connected to the router. I use an Apple Airport Extreme setup. And I found out that my speed was diminished due to I had a Vonage box between the cable modem and the Airport Extreme. The Vonage Box I found out was a bandwidth hog. Removed the Vonage box and rerouted it to the back of my Airport. And then all the sudden my Wi-Fi speed increased by 50%. Check to see what you have connected to the router.

The only thing hooked up to router is the network cable that goes to the computer.

On average what is a good percentage of speed we should expect from a router relative to the direct connection?