another arm/cart question (long post)

Hello all. I've gotten some good advice here for 2 of my tables and would like to hear from the experts again. I've just built a Thorens TD124. Its got a rebuilt motor, main platter bearing upgrade with sapphire bearing and Torlon thrust pad. MK2 motor spring upgrade kit, Audiosilente idler wheel, new mushrooms and grommets, and an Ortofon plinth. New armboard on silicone O-rings, and a fully rebuilt, rewired SME 3009 series 2, unimproved, with an effective mass of 12.5g. The arm has the FD200 fluid damper kit, but its not currently attached. For an initial setup, I put an old Ortofon 540mkii on it and it sounds very good. In fact its close to my Sumiko blackbird low, and AT-OC9XML on my other admittedly lower quality tables/arms. Phono stage is the built in one on a Mcintosh C47, which is quite adjustable for MM or MC. It runs through 2A3 tubes into Altec A5s with modded Hiraga crossovers. Being impressed so far with the 124, I wonder how much better it can sound with a cartridge upgrade. I love my Blackbird and thought about a Starling, but am open to advice. My budget is only 2K for the cart and Ill need to purchase another headshell and wires, so maby $1800ish for the cart. I've studied the resonance charts and know that only gets you about halfway there. I don't have test equipment, only my ears. The chart shows a good match with the starling but Id love some advice. The last 2 times i sought advice here, I followed it with amazing results so thank you all for that !  Also I've raised the arm, and added a 3mm mat to increase the distance from the magnetic platter to the cart for when I upgrade it to MC.  I'd like to know if I will have a good combination with the Sumiko Starling, and if not, which cartridge would you choose ? Fire away !