Air Tight PC-1 Coda and more options to upgrade my analog setup

If you are completely set on a low mass turntable and know that's what you prefer, then by all means wait for the new Regas.  However, the new Regas will be no different from the old Regas, in that they will have the exact same philosophy and likely the exact same performance.

That being the case, in my opinion you will never realise the full potential of a top-of-the-line low-compliance cartridge on a Rega set-up.

If I was in your position, with a comparable budget, I would first get a phono stage, then a new arm/turntable and only then begin thinking about a cartridge upgrade.  The way you're doing it now seems awfully backwards if an optimal result is what you're after and can only unnecessarily complicate the process.

Again, in my subjective opinion.

I'm not sure where this fear of fussiness comes from, or in what sense a Rega set-up is less fussy than many, many others.  Sure, you can certainly put together a vinyl rig which is very fussy indeed, but conversely there are any number of combinations which involve no more fuss than anything Rega.  Significantly less really, if you count the ability to easily change VTA towards the unfussiness score.

I’d like to echo these opinions:

I wouldn’t put an $8500 cartridge on a Rega

the cartridges you are considering are not a proper match to your tonearm

Rega tonearms are not a great match with low compliance MC cartridges, and the lack of easy VTA adjustment makes it difficult to optimize the VTA, which is crucial to getting the best from your cartridge.

The Luxman EQ-500 phono preamp is a great sounding piece of equipment.

I’ve never heard the phono card, so can’t comment, but it’s basically impossible to build an add-in card which performs to the standard of a dedicated phono stage. Hence I think that auditioning some top flight phono stages is even more important than chasing a new cartridge.

Along with the EQ-500, which is superb, I’d suggest you listen to the EAR 324, Manley Steelhead, ASR Basis Exclusive High Voltage and Air Tight’s own ATE-2 + ATH-2/ATH-2 Reference step-up. Or, if money’s truly no object, Air Tight’s new ATE-3011 + step-up and the Allnic H-7000V.
I’ve not heard the last two, but the five former phono stages are the finest I’ve ever had the pleasure of listening to.

From the PC family I’ve heard the PC-1 and PC-3, but none of the others. Fabulous cartridges and one thing that’s certain is that I would never put one on a Rega, be it an arm or a turntable. These cartridges really want a high mass design and a medium/heavy or heavy arm to shine at their brightest. High mass designs are generally also low fuss designs, so that shouldn’t be an issue. Personally I heard the PCs on a Nottingham Analogue Dais with a Kuzma 4Point, which to my ears was a match made in heaven.

There’s no shortage of high mass turntables, but my two favourites are the aforementioned Nottingham Analogue and Acoustic Solid. Obvious medium>heavy tonearms to partner them with for use with a PC-1 might be the Kuzma 4Point, Origin Live Enterprise or Agile, Helius Phaedra, Thomas Schick or the Dynavector DV-507 MkII.

Anyway, that’s my 7 or so ¢. All in my subjective opinion of course.

The Onyx Platinum is a great cartridge; I had one on loan for a couple of weeks and it sounded lovely.  I wouldn't personally pick it over a PC-1, but that's entirely subjective of course.

What isn't, is that it's both heavy (12.5g) and stiff (compliance of 5, presumably @ 100Hz, so around 8 @ 10Hz).  Not in at all an ideal match for any Rega tonearm I would have thought.....

Still, open to feedback and suggestions.

In terms of a potential change of turntable, my suggestion would be to listen to a high mass design .  If at all possible side by side with a different design.  Whether or not you'll find it preferable is anybody's guess, but given the $$$$ involved here it seems weird not to do so.  Particularly given the prevalence of high mass designs among the turntables generally considered to be among the very best.