I have to agree with Arthur somewhat. Both in the fact that although the Jolida is not as transparent, detailed and resolving as other higher priced players, it is also about as warm and emotional sounding as you will find from a digital device.
Modded players will tend to make this player more SS in sound. Many have said this before in the theads and my listening to a fully modded level 2 bears this out. What I heard in increased dynamics and bass, I was horrified at the loss of warmth and sweetness in the upper mids and highs, and the narrowing of the soundstage. Your level 1 mod surely is not as pronounced, but still changes the midrange of the JD's sound.
In my system, which runs all tubes, what the Jolida may lack in terms of detail, it makes up for with its warm and textural presentation. Synergy is key, and often times not all the gear works together to get that mix of emotional conection to the music.
It must truly be dissapointing to have spent a small fortune rolling tubes in and out of the JD.and still not get what you want.
I wish I were able to recommend another player, but aside from my former Wadia transport and Electrocompaniet 24/192 DAC that had better dynamics and higher resolution and focus, yet was not as warm and engaging a sound as the lowly Jolida player..I have no real answers to offer.
I did find ( after much rolling like yourself) that the best tube for the JD in my system was a pair of Cryo'd Ei ECC-83 Gray plates from ATSI. This tube blows every NOS tube.. Mullard Cv4004. Brimar, Amperex and all the 5751's Sylvania's, RCA's and Raytheon's out of the water with a GIANT increase in transparency while keeping the midrange magic of the JD. Depth and soundstage are wide open and deep and sound remarkable from this tube.Much smoother highs are very apparent over the non cryo'd tube.
I suggest you try a pair of these for $39.00 a pair, as a last resort, and then decide if you should throw in the towel. Another suggestion would be to think about a switch to tube amps perhaps and see if that does the trick. You have a great system, but need to find the right mix to bring the emotion and transparency in the same room. Sorry I could not be more helpfull.
Best of luck--Ken