Hello again, masi61... I reread your inquiry a few more times. There is a case to be made for selling the Linn and buying, say, a good used SL-1200 and investing in a really good cartridge, for example. I was given a 1978 Linn and have returned it to service. It’s been an entertaining process, though it has taken time and money to get to the point that I am satisfied.
I already own a great MC cartridge. In the past year and a half I have tried three phono preamps.
For the Linn I have added the Hercules PS and motor and a Cirkus bearing well and Edmund Chan inner platter. And a Tiger Paw bearing relief kit. And expensive platter and headshell mats. Money-wise that’s about $2100 all told. I installed the TP assembly and Cirkus bearing well and inner platter myself and probably could have done the Hercules myself too. The Linn rabbit hole.
I live no more than 10 miles from no fewer than one Linn dealer and three other Linn “experts.” My experience has been hit-or-miss with these experts.
So, depending on your time vs. budget priorities it’s worth considering an alternative to the Linn.
That being said, I really like my LP-12 and have no plans to replace it or upgrade it further. It sounds great. Good luck and have fun!