I recommend a tube preamp as well, I think if your not careful you could be adding a lot of coolness and edginess to your system. A tube based pre would add much needed warmth and the Modwright is a good choice but I would also check out a Manley Jumbo Shrimp, or a Doge 8 clarity, or Dehavilland Ultraverve 3 or a Audio Research or Conrad Johnson. All well within your budget.
Matt M
Matt M