First "audiophile" system, now what? Suggestions for best "bang for the buck" upgrade?


After being beguiled with mp3s and the TV AVR, I finally realized I missed having a dedicated stereo system. With a budget of $2400, here is what I put together:
  ProJect Carbon 1 w/TizoAcrylic platter and Ortofon Red cartridge,
  Hagerman Bugle2 preamp,
  Vincent V-60 tube amp,
  Martin Logan 12 speakers.
 No special wires or cables. My room is 14x19 that is open to the kitchen. Compared to what I had been hearing, this system sounds fabulous. But now I want more fabulous. So I am writing to seek help on making short term/long term plans to upgrade. Short term means the biggest improvement in sound that costs $500 or less. The long term plan could cost maybe $2-3k or more. I have read that going from Ortofon Red to Blue might be a an inexpensive but very noticeable improvement? If speakers are my weak link, then maybe Martin Logan electrostatics would be good (when my ship comes in)?
I welcome any suggestions.
128x128etwilley
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I'm just saying that to present digital to your friends in combat with analog then it should surely be the Vivaldi 4 box system from dCS...with of course suitable cables. Additionally it is not sufficient to represent analog with a QLY5F. 
I wasn't even born in 1967 so fair play to you sir for building an amp.
You have been given a wealth of great advice already. I will say in 35 years in this wonderful hobby, the biggest difference maker in my systems has always been speakers. Amps, yes. CD players, yes. Cartridges, to a point. The room, certainly! However that's a bit tricky to tackle with a family and real world issues. Personally, I'd look to speakers first that are compatible with your amplification....

I’d save up for better speakers. Lots of options open up when you have $2k to spend. Also - don’t limit yourself to just Martin Logan.
Good Day Etwilley,

If you are absolutely serious - embrace that this hobby is a series of long term strategies that require patients and knowledge.  If you want the best bang for the buck, start by investing in Power, Power Power. Realize that $500 is not going to much of anything for you at this stage.

Take the $500 save it, start a fund so that you are making sage decisions on building a solid power delivery system. Power cables, power distributor - not conditioner, Interconnect cables and speaker cables. Once you have that set, then look to the components, speakers etc..

You will save significant amounts money by working from a position of strength. If you know you have great power feeding your system, the easier it will be for you to know which components / speaker etc. are the best for you in the long run. Enjoy your journey and have fun.