I agree with others, stick with MM now so you can stick with mid or higher compliance cartridges for your existing arm, get a nice MM now, and later, when you move to a new TT, new arm, make sure the arm is good for mid/high compliance cartridge (likely).
sticking with MM, and Audio Technica
I have and love the sound of AT440ml microline stylus on aluminum shaft, currently using it every day on my office system.
AT540ml is the current version, microline/aluminum shaft/plastic body
IF you simply upgrade your existing cartridge’s stylus, it would be equivalent to 540ml
AT740ml is same as 540 except it is a cast aluminum body
https://www.audio-technica.com/cms/cartridges/09079f798b312248/index.html
the next logical step is a lighter/stiffer shaft like boron, ....
................................
don't forget the improved traceability of advanced stylus shapes, follow and stay in the grooves.
sticking with MM, and Audio Technica
I have and love the sound of AT440ml microline stylus on aluminum shaft, currently using it every day on my office system.
AT540ml is the current version, microline/aluminum shaft/plastic body
IF you simply upgrade your existing cartridge’s stylus, it would be equivalent to 540ml
AT740ml is same as 540 except it is a cast aluminum body
https://www.audio-technica.com/cms/cartridges/09079f798b312248/index.html
the next logical step is a lighter/stiffer shaft like boron, ....
................................
don't forget the improved traceability of advanced stylus shapes, follow and stay in the grooves.