Turntable - The Next Step

If you're asking what single upgrade would yield the most cost-effective benefit to SQ, I'd suggest a new cartridge.  Another bang-for-bucks upgrade would be to get an LPS to replace the wall wart on your phono preamp.  MS sells one that would be compatible with any other pre in their line-up.  You could also go (much) cheaper with a similar voltage after-market LPS, but as with all things audio, you may not get as much improvement.

I'll second the Music Hall MMF-7.3. It's a fantastic turntable for the money. To me, the Ortofon 2m Bronze it comes with is one of the best cartridges I've heard at that price point. It does everything right in my book. I have the MMF-7.3 In walnut veneer, which I like better than the black. It is a very well thought out design. I pair it with a tubed phono preamp, the Tavish the Classic with NOS tubes (RCA 7025, GE 12au7, and Sylvania 5751). 

I was quite shocked when I threw caution to the wind and upgraded my turntable set up from the Rega P3 to a Clearaudio set up. The sound stage and overall improvement in the clarity of high and low frequencies was outstanding. Good luck.

Take a look at the Marantz TT15. Made by Clearaudio. The price has gone up a bit (like everything else) but I think it's still one of the best bargains in turntables. It's a lot of turntable for under $2K.

If you’re gun-shy about MC cartridges, it may be because you’ve operated one with a wall wart. I did this with a Project Phono Box RS and it was terribly noisy. I bought an LPS for it and this did help overall quietness with MM cartridges but I still had loud hum with MC types.

I heard about the Hagerman Trumpet MC and its ability to stay quiet with a wall wart as part of its novel power supply design. Well it is pretty damn quiet. More importantly it sounded very sweet and musical.

This allowed me to finally use my AT33PTGII that was relegated to the drawer for almost a year. Finally hearing what a good MC can do is enlightening. I’m coming from years of commitment to the excellent VM740ML and VM750SH. Having a dedicated MC phono preamp is worth while. Keep your existing phono preamp for MM but consider a good MC specific unit and you may convert to the detail retrieval MC carts can offer.

I've found that MC carts are so sensitive that dust the cantilever picks up from normal use will slightly deaden the response. I use a soft stylus brush to gently clean the stylus and cantilever every few records. VTA/VTF setup is also very important. Buying a 4.5mm mat for my setup helped immensely. But once you understand how much more influential these little details are for MCs, you may never go back to MM.