Stick to your Oracle Delphi mk II and Graham Excalibur. To jump up to a higher class would cost you more than $ 2000. It would be better to invest money in a fine new cartridge and/or new phono pe-apm. As you mentioned, you would need higher output MC cartridge (I have/use also high output cartridge - Benz Micro Ace H). The alternative is (with low output MC cartridge) an additional phono pre-amplifier. Re-wiring with better phono wires can also improve the sound.
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