Does it make sense to run a 3k cartridge on a 2k table?

No problem. I’ve run Koetsu Onyx on a 25 year old SOTA Star. It was awesome and yes the Onyx was able to show off and beat up on more modestly priced cartridges. But be aware that tonearm and phono stage quality & matching will become much more crucial to get the most from your high-grade cartridge - THAT’s where you can get into trouble, and you need to do your research. The Fidelity Research arm I had on that SOTA made the pairing work.

Honestly once you get to a solid deck like that (Space Deck should be nice) you can run away a little with the cartridge if you’re careful.

That's kind of what I was thinking myself Tbh.

I am pretty sure the Spacedeck is my keeper.

Running standard Spacearm on it and using a Walker speed controller.

My thought process was along the lines that I was mote likely to hear a decent sq increase with a more upmarket cart than changing out the table.

Always nice to know I am only slightly crazy and in good company.

Present phono is Goldnote ph10 which is very flexible.

Have you considered the Blue? 

A considerable step down from the Purple Heart in cost, but still a very good performer. I hear it as a neutral, convincing cart on my setup.

Personally, I won't  go over half the retail of my table.

Another cart that performs above its price, is the  Audio Technica ART 9. I used one prior to the Blue, and it's another 1K less than the Blue. I have the Blue because the opportunity to get the Blue for a great price presented itself.

While I like the Blue more than the ART9, I don't think it's worth over 2X retail cost.

Presumably, your phonostage is up to the task for your next cart?