Hello Peter,
Don't you love our curse? No matter how good my system sounds I'm always careful to never let my wonderful (and indulgent) wife know that I'm completely satisfied. Terrible, I know.
I had an Exact cart which was my first 'good' cartridge and it was an 'aha' moment because I finally understood what all the fuss was about regarding vinyl. Then I moved on to a Clearaudio Maestro v.2 and it was a great upgrade. After another year or so my curiosity about the MC mystique compelled me to upgrade again. I considered many options, some costing over $3k, but I settled on the somewhat overlooked Rega
Apheta v.2. Nice thing about a Rega cart is that it can be installed with a greater level of confidence with its three point mounting. I LOVE this cart. It's very detailed, energetic, dynamic and just plain fun.
Also keep an eye out for an ultrasonic record cleaner like the AudioDesk Systeme. If you find a good used one you may find it as much of an upgrade as a new cartridge.
~Oran.