IMHO, you might find it impossible to find any cartridge, that would be close in performance to your phono stage, AND your TT could give it a justice. Short way to the answer to your question would be to ask other who have same phono stage (and at least speakers) what they use, but that would be misleading. What I can understand, you need something that will be more engaging - something that will make you listen to the music, not your system. Unfortunately, in this case "the source" in your system is not only the cartridge; it has to be looked at as a system consisting of cartridge, tonearm and turntable.
1. Rega turntable and tonearm is most likely the weakest link in your system - judging by your phono stage
2. Rega tonearm and its overall capabilities is too restricting
3. XP-17 is a very nice piece, and it shoots way over your TT. It can accommodate any and all of the cartridges mentioned here, from Sure to Koetsu. Is it one of the best phono stages ever? - definitely not, but it is damn good one
4. If you are emotionally attached to that Rega, Ortofon Cadenza Bronze might be the best choice here of all mentioned cartridges, if you can (and want!) to shim your tonearm to properly accommodate it
5. Any kind of the upgrade you can think of, including rewire of the tonearm, is not going to suddenly make your tonearm a "giant killer". Heck, it will be bested by a modest Jelco...
Before I went to Koetsu, I played with all kinds of upgrades to Denon cartridges. Best results I achieved were with DL103R dressed in closed black Ebony body and rettiped by ESUK with their TOTL boron / Paratrace rebuild; it is much better than factory 103R, it bested my Ortofon Quintet Black. However, I bought Koetsu Black Gold line - to see what is all the talk about - more or less for the same reasons I started buying all the Denon cartridges worthy of rebuild...
Soon after, I sold of all of my other cartridges - Ortofon, Clearaudio, Sumiko, Denon... Now, my daily driver is Koetsu Rosewood Signature. Is it the most "correct" cartridge I ever had? - no. Most expensive? - no. But with it, I enjoy music the most.
So, save a bit more and invest your money into the turntable, tonearm AND cartridge upgrade. It does not have to be something really extravagant, exotic and expensive - but it might. When it makes you forget your system, you are there.
New Phono Cart with Character Needed
I want to replace a Rega Ania MC phono cart on a Rega P3 because the current setup is lifeless, flat, and un-engaging. Phono stage is a Pass Labs XP17. The music produced currently is full of detail, very lifelike, instruments all sound very real, good upper end extension, but there is no there there. I can plug my phone into my multibit DAC and stream Jazz Groove and have a better experience because the sound is richer and has more oomph. I want warmth, oomph, texture, and wows from my analog. The Ania is just too flat, clinical and dry. I want to trade that for some color and a little more strength behind the notes. Budget is $1000. I mostly listen to Jazz. All suggestions are welcome.
Rega Ania MC Cart specs: Input Load Impedance 100 Ω, Output Impedance 10 Ω, Nominal output voltage 350 μV, Tracking Pressure 1.75 - 2.00 g
Rega P3 has been upgraded with GrooveTracer delrin platter and subplatter.