Much better MM cartridge than Shure V15 IV?

Hi, I have a Pro-ject 2 Xperience turntable, and I'm running a Shure V15 IV with Jico SAS stylus on it. I'm wondering how much higher quality MM cartridge can I attach to the carbon Pro-ject 9cc arm without exceeding the capabilities of the turntable/arm combination? Grados tend to hum on this deck unless I shield the motor's EMF. I have not tried anything else yet. What would you suggest as a clear significant cartridge upgrade?