I wouldn't do a MM if you can't adjust capacitance loading. A HO MC like a Dyna 10 or 20 sounds great on a Rega arm and if you like the Dyan sound (which I love) maybe the 10X would be worth a go. It won't be much of a departure in house sound for you, which IMO is such a big variable and risk for you if you go with another brand cartridge like Ortofon, AT etc. I do find the 20X HO is very sensitive to impedance loading with my phonostage just like the LO would be, but if it didn't sound too bright for you with whatever phonostage you have (I'm assuming you left it at 47K and can't adjust it) then maybe the 10X won't be either.