Where to best upgrade - TT, arm or phono stage?

I have a decent analog source (Roksan Radius 5 table >> Soundsmith re-tipped Clearaudio Virtuoso Wood >> NIMA arm w/Incognito wiring >> Bottlehead Seduction w/CS4). The cartridge is a keeper and I must stick to the "MM" paradigm.

I am considering the new Bottlehead Eros phono stage, which I can afford by selling the Seduction and a few odds and sods.

Generally speaking from your experience, at my level of analog gear which upgrade would yield the best bang for the buck:

Table (this seems the most costly to upgrade, but many of you have more knowledge here);

Arm (a Roksan Tabriz ZI is the only true "drop-in" I know of for my table and a used one is available for $750);

Phono Stage (the Eros costs $500 more than the Seduction);