The Denon cart is an overachiever as is your phono preamp. My advice would be to upgrade the turntable/tonearm.
Next ANalog Upgrade Question
I have a 2 year old Thorens TD-190 with a Denon 103R cartridge and the interconnects were upgraded (hardwired) with Audioquest King Cobra cables. Musical Surroundings Phonomenon II preamp into a Cayin integrated amp. I really like the sounds, but my question is where should my next "analog" upgrade be that provides a noticable upgrade in sound quality? A new turntable,cartridge, preamp?