Should I sell my Thorens?

I have just completely rebuilt my system & moved it into my office. I have been downsizing so I figured I could let my VPI HW19 MKII with a Premier arm & modded Grado cart go. Well I ended up with a Thorens 160 with the original arm & Grado blue cart, that is supposedly set up by a pro. Upon listening for the first night I was horrified to hear it. The turntable sounds fine on simple passages but once it get's busy the sound starts to dissenegrate. I was listening to The Grateful Dead Europe '72 album & as soon as the band starts to pick up the pace the music becomes blurred, to the point of white noise/static. I cleaned the disc & listened again hoping the sound would improve but it did not. So I swapped out discs & found the same exact thing on another album, great when it is a vocal & guitar but static when the rest of the band kicks in. It was so bad I switched over to CD.

So my question is, even if I pay someone else to set the deck up & possibly even tweak it will it ever compete with what I had? I could also sell it & buy any number of decks in the under $700.00 range such as the Rega's, will they be better dollar for dollar? As you can tell I listen to rock music, I prefer all the seventies clasic rock bands & obviously the pressings are what the pressings are from that era.

My new system consists of B&W CDM1 SE monitors, Zu Cables Wax shotguns, McIntosh 6450, Monster HTS 3500 power center, DH Labs interconnects, Onkyo SP100 universal player, Cambridge Audio 640p phono pre & the Thorens 160