I need some turntable guidance

A few thoughts, (spending not much at first).

a. I suggest what you heard in other setups, were not only 'great' speakers', but speakers properly matched to the listening space. That, for any speaker, is far more important than all the esoteric 'improvements' in the world, and most often less than ideally achieved. I would spend some time making sure you are getting the best out of your existing speaker location.

A test CD, a Test LP, and a decent Sound Meter are good tools to have forever. Get familiar with them before trying refinement. Do not go for perfection, just find what is happening and any acceptable location that improves things. Personally, I ALWAYS toe my speakers in, and tilt them back a bit, to avoid woofer reflection parallel to walls, floor, and ceiling.

b. nest improve your existing TT: Physical setup is far more important than anything else in ANY TT system.

practice setup skills with existing cartridge, then repeat setup with a new 'good' cartridge with a new stylus (your stylus is worn I suspect). You will use the new 'good' cartridge for a while on existing TT, then move it to your new TT, then in the future probably upgrade the cartridge, keeping the 'good' one.

You need to acquire these skills, for any TT, existing or future. Practice for eventual setup of a new cartridge. Acquire templates, stylus pressure gauge, transparent alignment block with horizontal and vertical reference lines/grid

Level TT; re-align cartridge in Tonearm Headshell, Arm level/parallel with zero tracking force and zero anti-skate; Arm height when floating parallel. Leave anti-skate zero when setting tracking force, then add a matching anti-skate force last.

Then listen with Test LP, especially left right balance which indicates both proper stylus/groove interaction and proper anti-skate to 'float' the stylus left/right in the groove.

...................

Now, when evaluating a new TT, concentrate on what makes you happy every time you glance at it, because, IMO, once a good cartridge is properly set up, improvements will be slight.

I didn't go thru this, but something useful might be in this thread

https://forum.audiogon.com/discussions/so-many-great-golden-era-dd-tables-out-there-what-do-you-recommend-fo?utm_source=sendgrid&utm_medium=email&utm_campaign=website

As you've discovered, there is indeed a wide range of opinion on what can be done.  I've owned your preamp and have years of experience dating from the early 70s with your amp and K-horns.  Here is some more food for thought:

Your C2300 has one of the very best phono sections ever made.  Good enough that Harry Pearson had one in his reference system for about a year.  A remarkable feat.  The MC section is especially good and features on-the-fly loading adjustment.  Use it and you won't be disappointed.

Your budget is huge and can accommodate the very best that's out there.  You will want to consider how you want your music presented.  My belief is that matching the cartridge to your speakers makes the biggest difference since they are the two fundamental halves of the transducer system.  The K-horns tend to be a bit bright and will benefit from good definition at lower frequencies.  Consider a high end Koetsu or Dynavector.  Note that both require very precise alignment to deliver rewarding results.  Figure on $5K.

To get the best out of the cartridge, you will need a tonearm that has substantial set-up adjustability and delivers rock-stable repeatability on those adjustments. I personally prefer arms that have VTA on-the-fly, but you may not. If so, look at Graham or Tri-Planar.  If not, consider SME or Ortofon.  The VTA OTF and tonearms all have lots of thread input here.  Figure on $6K, and more for enhanced models.  You will also need a cable.  Lots to choose from there and I found a Cardas Golden Reference that suited my needs for $600 new.  I would suggest not spending a lot on a cable until you have the other bits and pieces sorted out.

The turntable must hold the selected speed endlessly and silently.  It may also have to absorb environmental vibrations (e.g footfalls, nearby truck or rail traffic, etc.).  For me that meant SOTA, which has one of the very best suspension systems ever produced.  I also prefer belt drive for that reason.  If you don't have those concerns, VPI, Pro-Ject, Clearaudio, Basis, Thorens and certain vintage gear might be appropriate.  A brand-new SOTA Sapphire sells for $4K loaded.  Vacuum versions are about $5K.  The other brands also sell in a similar range for very solid products. Surf the forums here for info on whether the vacuum system may be right for you. 

FWIW, I believe the biggest improvements are to be found in the cartridge and tonearm.  They combine to control the point of contact, and that's where Edison's science happens.

Hope this input proves useful for you.  Keep us posted on your progress and enjoy the adventure; remember always this is a hobby.  Happy listening!

effischer, the Koetsu requires a considerably heavier arm than you would put on a SOTA. The Ortofon Windfeld Ti is very neutral, will match up with just about any system and is one of the best tracking cartridges you can buy. It handily out runs my Koetsu in that regard on the Hi Fi News test record. It also works well in a wider variety of arms. I would not consider a unipivot arm at all. If you look at Lyra's web site you will notice that they specifically recommend against it. The Triplanar and SME are excellent arm but IMHO the 4 point 9 is better and less expensive.

Wemfan, as you noticed people like to wax poetic about turntables, tonearms and cartridges. Just look at the finest, most expensive examples of each. All of the finest, most expensive turntables are belt driven, not direct drive and not idler wheel. Look at the SAT tonearm. Big stiff tapered tube and rigid bearings. Check out the cantilever of the Clearaudio Goldfinger or the Air Tight PC-1 Supreme. Tiny diamond glued right to the end of a boron cantilever. No excess material. Now look for those traits in more reasonably priced equipment. 
For set up you will need a good protractor. I like the DB Systems. A pocket mirror, a digital tracking force gauge, a bubble level and tools usually supplied with the tonearm. If you get a SOTA you can tell them what arm you plan on using and they will drill the arm board for you.

Mike