I'm going to be a bit of contrarian and say that if you go MC, I would avoid the HO carts. The extra output is obtained by more windings on the coil. More windings = more mass = more inertia = slower response = smeared transients and diminished microdynamics. You're basically sacrificing the characteristics that MC carts are known for.
Check out the KAB cartridge gain calculator on line and plug in anticipated overall system gain. If your amp and/or pre is high gain, the MM stage may work just fine. Also, there are phono stages w enough gain that you don't need a separate step-up.
OTOH, if you're just dipping your toe in, then a lot can be said for a good MM or even an MI cart from Soundsmith, using your current AI phono stage which is reported to be quite good.
Check out the KAB cartridge gain calculator on line and plug in anticipated overall system gain. If your amp and/or pre is high gain, the MM stage may work just fine. Also, there are phono stages w enough gain that you don't need a separate step-up.
OTOH, if you're just dipping your toe in, then a lot can be said for a good MM or even an MI cart from Soundsmith, using your current AI phono stage which is reported to be quite good.