Turntable versus tonearm versus cartridge: which is MOST important?

Like everything else in audio, there are extremely expensive examples of tables ($500k +) and tonearms ($70 k +) and cartridges ($20 k).  But, I think you can get quite close to state of the art sound at MUCH lower prices with a good table/arm/cartridge selection than you can with comparably priced speakers and amps.  For the $10 k budget, you do not have to make big compromises in sound. 

A local dealer who has assembled system well north of $1 million, and has many customers with systems costing more than $100,000, will recommend as worthy tables reconditioned Thorens 124 and Garrard 301 or 401 tables with Ortofon tonearms.  Sometimes the cartridge recommendation is pricey (Koetsu Rosewood Platinum), but still, the combination is much less than recommended speakers or amplification.  

A local dealer who has assembled system well north of $1 million, and has many customers with systems costing more than $100,000, will recommend as worthy tables reconditioned Thorens 124 and Garrard 301 or 401 tables with Ortofon tonearms. Sometimes the cartridge recommendation is pricey (Koetsu Rosewood Platinum)

He's probably too old 

He obviously does not do much work with subwoofers. 

Cartridge, by a country mile.

Had the opportunity to directly compare it in my system to a Clearaudio Performance DC/Satisfy Carbon arm/Lyra Delos cartridge. Total cost around $7K.

The latter was better in most parameters especially with respect to dynamics, detail, resolution. Tonality/frequency balance was more natural with the vintage system (less upper frequency glare).

Chakster beat me to it but yeah, this is the Lyra. Also to a lesser extent the ClearAudio. I have heard CA rigs like this that were scarcely better than digital.   

This brings up another thing, that I have been saying for a long time, that analog and turntables in particular are so good you can get great sound from just about any of them. Even more so if instead of spend spend spend on flipping components you tweak tweak tweak what you already have.   

The entire reason you got the answers you did, from me anyway, is the question you asked. Ask a different question, get a different answer! You asked a hypothetical when maybe would have been better to ask something more specific.  

You could for example get a LOT closer to the "dynamics, detail, resolution" of the expensive rig WITHOUT sacrificing any of the vintage rigs  " Tonality/frequency balance" (which is its strength) with a few select tweaks. Put that table on a set of Townshend Pods, put some Synergistic PHT on the cartridge and arm (I recommend Green and Black) put Origin Live Cartridge Enabler and maybe their Mat on it, and trick it out with some fO.q tape, and I think you will be surprised. Hugely surprised. 

If the goal is cost-effective improvement without sacrificing any of the great qualities you already have this is the way to go.