Ket, the advise of the previous posters (to not bother messing with a good thing) is wise. You would do well to listen to them, and either divert the money elsewhere or save up for speakers that might offer more of the sound you're looking for.
Nonetheless, if you're still looking at upgrading the source, I can recommend the Electrocompaniet ECD-1 DAC. Since you've heard the EMC-1 and generally liked it a little better than the MF, but not for the money, you would do better with the DAC. Used it is often a little under $1000, and supposedly has the same DAC as the CD player. The Rega Planet should function as a great transport. I own the ECD-1 and can attest that it is a strong, if not dated, DAC.
Alternatively, I would strongly consider a newer DAC. You MIGHT be able to get a previous model Audio Horizons DAC for under $1500. (I own one of these, too.) It offers both better resolution and musical palpability compared to the ECD-1. If detail is what you're primarily looking for, maybe a Bel Canto or Benchmark DAC would be to your liking. The good news with a used DAC is that you'd have the flexibility to both stay within your budget and potentially move to computer-based audio, and you could sell it for minimal loss. This would allow you to sample different options without losing much money in the process.