Your amp and preamp have good reputations, and one poster says they should be a good match. Others who know these electronics well are welcome to correct me, but if you are not satisfied with your sound I would not look to the amp and preamp myself. Instead I would consider either a source or a speaker upgrade, or both. Your Music Hall player, for example, is great at its price, but it's possible to do better still.
A DAC, perhaps but not necessarily a tubed one, would be an option, but you would have to add the price of a good 1.5m digital interconnect. You might find an Apogee Mini-DAC and a VH Audio cryo Pulsar cable within your budget. (I only mention the ones I know in that price range, but there are others of course.)
Otherwise you can find smoother, more 3-D sound going up the Shanling line. The tubed CD-T80 would be one big step up from the 25.2, the JAS Audio Musik 1.2 would be another. These and other one-box players retail around $1200 and might be found used within your budget.
If you could describe what it is about your sound that you don't like, that might help us to suggest alternatives.
