suggestions on upgrading my system

What do you feel is the weak link to you're system? I would upgrade my amp stage... This is what I have and I absolutely love this piece... http://nadelectronics.com/products/masters-series/M2-Direct-Digital-Amplifier

I believe the weak link might be the phono/preamp stage in your integrated.  Obviously different ways to attack this. Maybe getting a outboard phonostage 1st. Also can the amp be separated from the pre in the HK?

replace harman karden

What is your upgrade budget? 

I'm not sure what is my weakest link. I would think it is on the electronic side. I like my speakers, TT, cartridge, and sub.

I also have a Onkyo DX - C390 cd player.

Mesch, I'm thinking it is the phone stage with the HK. I would need to read up on how to introduce a seperate phone stage with my HK. How would that work?

Any sugesstions on a great phono stage?

I'll check out your suggestion Riglet11.

Is there anything I can add to the HK to imporve it or if I replaced it what would be a step up? Around $2000 is my target budget.  Hoping that could get me some good deals here on audiogon.