I had a Rega P5-the next step up from the P3.
Save yourself the hassle stay with the Rega philosophy. That means simple. Get a Rega cartridge. 3 screws,set tracking force-done
If your MC curious, then look at the Ania. Exact for MM
While any of those carts will sound nice, it is hit or miss, since you will also need to shim for VTA(if that's what you want to do).
Get a different table with adjustability if you want to really explore cartridges.