What's the weak link in my system?


     I've pieced together the best budget system I could afford over the years but I'm just not thrilled with the sound I'm getting. Can anyone help me identify the weakest link (s) in my system so I can upgrade? I only have the budget to upgrade one piece at this time. I'm most interested in listening to vinyl.
Currently Configured:

Pro-ject Genie 1.3 Turntable w/ Sumiko Pearl Cartridge
Bellari VP 130 Phono Pre w/ Tung-Sol Tube & Replaced Power Supply  
Marantz CD 6006 CD Player
Parasound P3 Stereo Preamp
Parasound A23 Power Amp
PSB T6 Platinum Speakers
Bluesound Node
AKG K702 Headphones
Audioquest Daimondback Interconnects
Audioquest Rocket 33 Speaker Wire

Also Have:
NAD C235BEE Integrated AMP
Monitor Silver RS6 Speakers
Marantz SA8260 SACD Player (Used to sound great but doesn't work consistently - not sure if worth having repaired)
Musical Fidelity V Can Headphone Amp


So.... I think I have put together the best possible system configuration using what I have. What would be the weakest link / first to upgrade? Turntable? Phono Pre? Pre-Amp? Suggestions of products to upgrade to without breaking the bank? I've accumulated a bunch of stuff but I'm really a novice so any and all feedback would be greatly appreciated!   

jdm11
It's funny you say that inna you're right on the money; I got called away on an emergency short notice business trip a couple days ago and just got back tonight to find all this informaion. I''m so glad to see the discussion and thankful for the interest and all of these perspectives. I'm going to need some time to sort through it all! 

@jdm11 - I totally understand. I had to leave for several hours, but before I left I just saw how you described what your "problems" were and what you wanted:

- CDs sound a bit harsh and thin.

- I’m looking for a more "3D" kind of sound with depth and warmth but clarity as well (not muddled or fuzzy).

If these are your problems, there are several things I can think of that could help you move towards your goal:

- power cords. If you are still using the stock power cords for your equipment (cd, preamp, amplifier), then looking at an upgraded power cord can significantly improve things. I have recently found that the Audioquest power cords which use solid-core conductors are an excellent solution. I listened to the Audioquest NRG-4 model before I re-terminated the ends with Furutech rhodium connectors. The stock NRG-4 cable sounds very nice. It has a very solid sound with warmth and power. The solid-core conductors ensure that music impacts hit with authority and power. The gold-plated copper connectors give a nice warm sound. I would avoid any of the power cords with silver-plated connectors in your situation.  I have gone through testing with many different power cord material and geometries.  Solid-core conductors win every time.  Stranded wire power cords can sound good, but they just don't have the same "solid" audio character and they sound very "lo-fi" and "digital".  I have tested this with a very high end Furutech OCC copper power cord.  They just don't work as well as solid-core conductors.

Stock power cords usually use very small 18awg stranded conductors and may not even be copper. The stock cord connectors are also poor quality. These stock power cords can introduce a bright/harsh character to the sound.

- fuse upgrade. This is only a slight suggestion as fuses are definitely a controversial subject. I have also found that stock fuses will sound bright/harsh. Although, the right choice of fuse can be difficult to determine. I usually recommend Isoclean as being a very nice warm sounding fuse. This may end up being to warm for you as it can roll-off the high frequencies in some scenarios. You can try the Furutech/PADIS fuses, but expect a 200+ hour burn-in and these fuses can be very fast and revealing to the point where the system becomes too thin/lean/cold. There are other fuse choices. I would avoid the silver Hi-Fi Tuning fuses in your situation because you feel you have too much harshness/thin character.

- Interconnects. If you want, you can start backing off from the silver-plated elements. Your Audioquest Diamondback interconnects have excellent conductors, but they do have the silver-plated connectors. These will conduct electricity a lot faster than other elements and will contribute to the very bright/thin character. If you want to look into this, I would say to get the best Audioquest interconnects you can that still use gold-plated connectors. The Perfect Surface Copper and Foamed Polyethylene Insulation are excellent items in Audioquest cables.

- switching power supplies. All of your listed equipment uses linear power supplies, but you don’t describe power distribution. Are you using a single power strip or going to different outlets? If you have any device with a switching power supply connected to the same power strip or outlet, this can cause your audio to have a bright/harsh digital solid-state character. These can be things such as bluray players, satellite receivers, or anything else that has a switching power supply or wall-wart.

I've need been in your position before. If your like me you probably think to your self, it sounds good but I'm not feeling the magic. 
I don't think changing one component is going to make the difference your looking for. What you need to do is start swapping out your gear piece by piece with gear that is a level or two above what you have. I get it, when you don't have the cash it's difficult. But if you look for deals and swap it it slowly piece by piece, it's do-able.
 For example I'd lose the amp and preamp and get a Classe,  Belle's 150a ref, McCormack, krell, exposure jolida or bryston for your amp or pre. I actually just bought a jolida tube pre for 400 and I love it.

Next unload the marantz, I've personally never found a marantz cdp that I thought was more than Mediocre. Instead if you want to stay with traditional cdp I'd get a rega appollo, exposure, naim or if you can afford it an older wadia. NAD had a pretty decent little cdp a few years ago, I think it was the 542 or perhaps there silver line. The best sounding and cheapest digital source I found was musical Fidelity v90 USB  dac on a computer using Jriver software. It was wonderfully dynamic and detailed.
Your turn table could be switched for a higher grade rega, but I'm not really up to speed in LP so others would give better advice on your LP player.
Your cables I would change to at minimum audioquest Columbia or similar grade Tara labs or harmonic tech, for your interconnects. and For speaker cables I'd look at Dh labs for a cost effective good cable.
  As far as your Speakers go, I'm not familiar with those, but you may get the magic out of them after you change your electronics. If not then you need to audition a few until your zero in on what you like in a speaker. If it were me I'd be looking at a pair of thiels, sonus Faber, Dali,  something a long those lines. 
Let your ears be the true judge of what you like. Obviously your not hearing the magic as of now, so something's gotta change. 
As far as what order, typically people say start with the front end, but I'd start with what you can get the best deal on first. If there's a sweet Classe or Belle's 150a for a great price, I'd get it, I wouldn't wait around for the source to come up. Buy the stuff as it comes available.
In closing I really think you need to break out of the midfi stuff before you'll get the twinkle your looking for. As you start switching stuff out you'll start seeing the improvements. 
Best of luck
Did you remove the power conditioning?  If so, what were the results?  If not, why?