I have a few friends who have Belt Drive TT's, I have shared this info before.
One TT is a Brand that is modern, one TT is a older model from a Brand and modified with OL Parts and the other is a LP12 of similar vintage as your own having undergone some of the available upgrades (note Linn are not the only Company with Upgrades on offer for the TT).
The demo'/comparisons were far from perfect, as a result of using different Tonearms and Cartridges on each TT.
The outcome reported from the attendees was that there was not too much to be discovered, and the Linn was as attractive in use as any other being demo'd.
There might be discovered within the Link some info that inspires you to keep on with the Linn.
https://www.diyaudio.com/community/threads/linn-sondek-diy-mods-that-work.272570/