Phono preamp suggestions; can I improve upon my Aesthetix Rhea Sig ?

Good to know your are heading toward happiness and remaining with the Rhea.  I also have had a Rhea in my system for many years.  I recently bought a new table and thought about the phone stage also but decided to get the Eclipse upgrade.   Haven't got it back yet but I hear and read that  the resolution is incredible. 

Skinzy my Rhea Eclipse is scheduled to be returned on the 10th and I am sitting on the "edge of m,y seat."  Given the pandemic. parts, and staffing the turn around was 12 weeks instead of the usual 6.  Aesthetix has advised me that the complete break in is approximately 400 hours with 80% at around 250 hours.  Like you my Rhea is 16 years old as well.  They report the Signature upgrade doubles the standard Rhea and the eclipse doubles the signature in terms of resolution.  Out of the box they report improvement in sound-stage depth and extended bass although less controlled  but "really" improves in a short time.  I'll see how my sub reacts.  Anyway I'm keeping you updated as requested and let you know how it sounds.  FWIW I have a Basis 2800/Vector 4 Arm/Hana Umami Red and my "go to" is "Jackson, Johnson, Brown & Company issued by Pablo.

Skinzy I rec'd the Rhea Eclipse yesterday and only put 5 hours of listening on it so far.  I had taken a pic of the standard Rhea before the upgrade so I immediately noticed the significant changes in circuitry. The 2nd thing was the complete elimination of tube rush from both channels; dead silence  It was returned with JJ tubes where I had Teslovak E83CCS/Sovtek 6922.  Per Aesthetix the J's offer them the lowest harmonic distortion based on a per batch selection. An appreciable improvement in resolution was immediate as judged by a reduction of sibilance, and a smoothing (less lippy) of JJ Johnson's trombone solos.  In addition certain passages were presented/emphasized in manner different than before.  Mid bass definition improved based on an increased overlap between the Maggies and Vandersteen sub where there has always been a slight hole. Deep bass was solid but inconsistent in that it was more impactful/defined on some and not on others. Overall this seems to be consistent with the initial expectations Aesthetix delineated.  Once again they say it will get better "every day."   Again my comparisons are with a stock Rhea I've had for 15+ years.  FWIW their customer service gets 5 stars!