if you had my system and $2,000 budgeted for an upgrade, where would you spend it?

This post may go a bit beyond analog, as it could encompass other parts of the system, but I am not interested in adding to the digital side of things, so here it is.

As far as I can tell, it seems like the places to spend that $2K would be on a better tonearm or perhaps a preamplifier upgrade.  I may be able to sell my Audio Research LS-25 and upgrade to ARC Ref 3.  As for the tonearm, I could sell the RB202 and get a Michell Tecnoarm, or step it up to an arm for about $1600 (are the Clearaudio arms nice?) and still have a little left over.

Can a tonearm upgrade make a significant sonic improvement?

I am not dying to spend money on an upgrade, and if the benefit of that $2K will be minuscule, I am happy to stay as I am for a while, my system sounds excellent.  But I am curious to know what the experienced people on this site would do the the $2K if they were in my shoes.

Where is the most improvement possible?

System Gear List:

Amplifier:  Audio Research VT-100 mkII
Preamplifier:  Audio Research LS-25
Phono Stage:  Whest Audio PS.30R
Cartridge:  Lyra Delos
Table:  Michell Engineering Tecnodec with standard RB202 tonearm
DAC:  PS Audio PerfectWave DAC mkII
Power Conditioner:  Shunyata Research Talos
Speakers:  Rockport Technologies Mira Monitors
Subwoofer:  Wisdom Audio SCS
Speaker Cable:  Cardas Audio Cross
Interconnect:  Cardas Audio 300B Microtwin XLR
Digital Music Storage & Player:  Apple Mac Mini + ROON + Hard Drive
Power Cables:  Shunyata Research Venom HC (amp, sub, conditioner)
Power Cables:  Shunyata Research Sidewinder VTX (sources)

My system can be seen here:  https://systems.audiogon.com/systems/5421
I am getting the feeling that the 300b IC cables are the weakest link, and that stepping those up properly to a better cable, with auditioning different options is a way to go.
To be sure that what I had to say about cables in my previous post is not misinterpreted, I'll add that I was in no way implying a perception that cables are the weakest link in your system.  Frankly, I don't know what the weakest link is.  As I said in my initial post in the thread, "While I have no specific suggestions regarding a $2K upgrade...."

Good luck.  Regards,
-- Al
I said the Cardas 300B cables are a weak link due to the fact that they are an old design Cardas cable. They roll-off the highs, lack low-end extension, and colour the sound. They were replaced by a much better budget cable, the Parsec.

These cables are limiting the sonics of your fine components. My point all along has been that until you decide what that next major upgrade in your system will be, changing to better ICs will make a noticeable improvement.
I recently purchased an AudioMods tonearm, which is a drop-in replacement for the Rega.  I find it to be a significant improvement over my previous RB300.