IME with Technics decks, Mats are a personal preference. I tried various on mine - from cork to leather to a Ringmat - and found either an Achromat or Herbies was best for my ears. YMMV as they say. I'd not buy a weight - it wasn't designed with one in mind, and I think the benefits of such can be spurious at best. I'd look at the cartridge for sure - bung a better stylus on there and live with that for a while until you can go MC (if you even want to!)... HOMC is an option too. The KAB damper will well and truly open up that world to you.
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Before you criticise a man, walk a mile in his shoes. Then, when you do - you'll be a mile away. And have his shoes.
Wavy grooves go thru a RigB 540ML on an SL1500C. Digits stream from a cheapie CDP and a Sonos, into a Yamaha 803D driving Kralk Audio little 'uns. I used to have a Linn but I'm better now.