Had MMF 2.1, need to upgrade

Looking for a little advice.

I've had a Music Hall MMF-2.1 turtable for about 2 1/2 years.
I've been quite happy with the sound. I'm running the turntable into a computer with a high end sound card (for recording), then out to a tube amp and speakers.

It's getting worn out, especially the cartridge/needle. I would like to upgrade and purchase another table. Should I consider replacing the cartdige, or replacing it all. Is the MMF-5 the next logical step-up? What other brands are comparable.

Thanks for the help,
Andrew (CO,USA)