Should I upgrade my phono pre??

My custom Rega with an Apheta v.2 sounds great and I sure have been enjoying listening to so many LP's on my stereo. My phono stage is an AD-50 phono option board plugged into an Accuphase E-470. But then in a moment of weakness I bought a table that I've kind of lusted after for a long time, a Luxman PD-171 with a 10" Jelco 850 series arm. The cartridge is an Ortofon Cadenza Black. After solving a vexing ground loop issue, and getting the cartridge dialed in just right, I was simply unprepared for a shocking improvement in every aspect of the sound. When I cue up a record I can't but sit transfixed by the music. 

So I THOUGHT that my Rega/Apheta was the bomb. I had no idea that the Lux/Cadenza Black would be such a thrilling upgrade. Now I'm wondering if I would get yet another leap in performance if I was able to invest six to seven thousand (used or new) in a new phono pre. The AD-50 SEEMS awesome, and I'm a sucker for anything Accuphase, so my question is: Should I be shopping?