Pre and Amp Suggestions

Given the way these things go, I’m almost afraid to ask this question but here goes: I’m finally at a place where my front-end and speakers are at “destination” level-at least for me....for now.  My question is where and what to upgrade between these two extremes. The speakers in question are Revel Studio 2s which I love, and the front-end dac/streamer is the Lumin T1 ruining Roon. The Lumin feeds into an analogue bypass section (no digital conversion) of an Anthem AVM60 going in turn to two 200 watt mono channels of a Sherbourn 7300. In trying to answer my question, I would appreciate keeping to the following parameters:

-no suggestions of other speakers or front end gear, I’m in a good place where I am right now.
-no suggestions of power conditioners, cables etc. Let’s just stick to the gear.

Just looking for pre and amp recommendations (or really good SS integrated amps). The sound right now is quite neutral, but perhaps a little lean but very revealing. I’m not looking to drastically alter the sound or play louder, just looking for more of the “good stuff”, resolution, staging etc. Might consider a tube pre or hybrid but really have no interest in an all tube power amp or massive class A space heater anymore. Ok let the games begin!
6SN7 tubes have a really nice sound. There are a few choices there. The fanciest on in your used price point would be Cary Audio SLP-05 Preamplifier. Beautiful 2 chassis design that has balanced XLR to amp.
Have you considered trying to upgrade your ri-100 to the ri-101? I was talking to the new US distributor (High End by Oz) and he mentioned the ri-101 had a revamped preamp section. You should give Oz a call.
I think I would only being upgrading with Vitus by moving to their signature (class A) equipment. The RI-101 would only be an incremental improvement. Thinking I agree with the tube preamp suggestions and keep the RI-100 as a power amp possibly