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

Congratulations on your new upgrades,

That is a tough call, because only you will be able to determine if something will be better in your system. Yes, typically, a more costly, or the next higher device in a lineup should sound better, but; that is not always true, depending on the system. 

If it were me, I would wait until you have the VPI HW-40 and Crimson setup and played for a while in order to make an informed decision to determine if something can be improved. You will not know which way to upgrade unless you listen first. However, many have taken a leap of faith, to include myself, to purchase what we felt would be an upgrade. You win some, you lose some. If you already like the Aesthetix sound, then it might be the next logical step to upgrade to an Aesthetix IO Signature or Eclipse. Of course, the XP-27 is also a nice choice. Take your time and enjoy the system for a while in order to inform your decision. Have fun listening to your new setup. 

I have heard an earlier version of the Pass Phono at a friends house and compared that to my Aesthetix IO Signature (now Eclipse with two power supplies) circa, 2008. I though the Pass Phono was an outstanding phono amp as it performed its duties, effortlessly. Compared to my Io at the time, I needed to ensure that I had very quiet tubes and minimized RFI/EMI radiation from cell phones, and other devices. The Io at the time was very sensitive to that type of interference. Now, with the Eclipse upgrade, the power supplies are more efficient, low to imperceptible noise, and upgraded gold caps, and Aesthetix matched tubes, wow, this is a vast improvement over the Io Signature from years gone by. I don’t concern myself with any stray emissions from whatever, it is just an absolute quiet device. The Io Eclipse of today delivers a big, dynamic, and holographic soundstage, with no noise. 
 

Going back to my circa 2008 time stamp when I compared the older Pass Phono with my Io, the Pass Phono is plug and play, while the Io needs some TLC to play competitively. One thing I liked the Io Sig from way back then is that it was more dynamic, albeit with some slight tube noise. Todays Io has no tube noise and is quiet. You can throw away the plug and play analog from the previous generation comparisons, because, now both, are simply plug and play as is. Of course, with Io, you have the luxury (or is it?) of swapping tubes. 
 

@skinzy 

Yes, the newer or upgraded (sent back to factory for refresh) Io phono amps are fantastic. Since you already have experience with tube rolling, you will find that you don’t have to with the newer Io Eclipse versions as Aesthetix is carefully matching tubes.
 

One caveat, I did have one tube in V1 start to whistle (after 30 days), and Aesthetix was going to replace it, but I ended up doing my own tube rolling anyway, and went with GL 12AX7s, which are outstanding in those positions. Other than that, I have not touched another tube and find the Io to be the one single audio component that has outlasted everything else I have owned for nearly 16 years. When you consider that, it is remarkable due to the enormous amount of tubes. It is a testament to the build quality of the Aesthetix Io series. 

@skinzy 

Glad that your new turntable and cartridge are settling in nicely and sound better than your previous configuration. Agree, love the experience of listening to new equipment and being happy after hearing improvements.