Upfront disclaimer: I own a Galibier turntable and Tri-Planar tonearm
I am familiar with the Rega P9 and it is a very good turntable. That said, the Serac/Triplanar combo will be a huge improvement. The Serac comes mighty close to the top-of-the-line Stelvio at a fraction of the cost. Also, you would be able to upgrade the platter as funds allow.
Finally, I can not say enough good things about working with Thom.
I would be glad to speak with you off-line...