What is the best tonearm for a SOTA Nova turntable?

There are many very good tonearms to be had for way less than your quoted cost of the VPI. Possibly even a used Triplanar or Reed. Certainly a used Dynavector, FR, Victor, or Technics, for examples.

Holmz, it’s actually voltage based amplification from cartridge to speakers, if you exclude the aforementioned low internal resistance, LOMC cartridges. Although even that’s an oversimplification.

At least one site says;

The magnets + coils assembly constitutes a miniature current generator

I finally got the Kiseki mounted and set up. It sounds pretty nice. I listened to "Cantata Domino" and Jazz at the Pawn shop, both Proprius recordings. I'll listen some more this afternoon, but my comparison to digital streaming is still that with digital, voices and instruments come out of a darkness that analog can't match. Of course the dynamic range of digital is much better. Soundstage and imaging is better with digital as well. But perhaps, analog sounds a bit more real.

I doubt that a new table  or arm, or phono stage is going to fix these deficiencies unless I spend a whole lot of money. 

Holmz, you could change the predicate of that sentence you quoted to …”constitutes a miniature voltage generator “, and the sentence would be equally correct or incorrect. It’s the impedance at the interface that determines whether you’re in current mode or voltage mode, and apart from the special case of a LOMC cartridge with very low internal resistance driving a current mode phono input with an even lower input impedance, downstream devices drive a high input impedance, in voltage mode.