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
I have a budget system, too (WAY more budget than yours!). So maybe my experience will be useful.

I went with the advice I was getting, that the turntable and arm are the most important item in a vinyl playback system. Which meant replacing an old Technics with an old Thorens TD-160 (I told you it was a budget system).

Then I kept following the advice, which was to get as good a cartridge as you could afford. I was enjoying an old Grado with upgraded MZ8 stylus ($200 here in Canada!), which has a very attractive warmth and depth (as others have noted), but when a Linn ASAK came up for sale for $50, I bit.

Then I needed an MC preamp, so I bought a Pro-ject Phonobox S, but it was WAY too noisy. I found a Rotel receiver with an MC stage, for dirt cheap, so I am using this until I can afford a big ticket item like an AR tube phono stage (my Tannoys are bi-amped, with an old Electrohome SET amp powering the aluminum horn-loaded tweeters, and an old Nikko Alpha II powering the woofers. It sounds very nice.

So, long story short:

Best Turntable/arm you can afford
Best Cartridge/Preamp you can afford
Then the regular order - speakers, amps, accessories/room treatments

Hope that helps.

after months of torture in winter i found that sound improved greatly with the increase in the relative humidity in the room. Was generally about 20-30 % in winter, and around 50% in summer. so get a humidifier would be my advice. not only the stereo equipment itself but also all the furniture etc affects what you hear. obviously sound bounces off them. 

If you don't know ... then nothing is weak.    Once you hear something, you will know.
There are so many things to consider. Always make your front end the best u can possibly afford. If it starts out crap, u can't hope for anything more at the end. Not saying your cart sucks, but invest in the very best u can. I had the preamp u are using and it sounded good for what it is. High current amps and good speakers are a must. I realize, this comment doesn't give u a lot to go on, just saying. As with women, the front and back end are a must. 
Agree with Handyman.  The front end is probably your weakest link - both analog and digital.  I owned the Bellari and found it lifeless. Did not keep it. Get a good solid state phono preamp, like a Dynavector DV-75, used. I prefer tubes, but good tube phono preamps are expensive. For digital get the best dac you can afford. Everything else should be ok.