Next Upgrade to My Totem Arros Setup - Need Help

Hi,

I need your expert help in upgrading my stereo set-up. I like my current set-up immensely.

My System: Totem Arros, Primaluna Prologue 2, Signal Cable, Hero Inter Connects, old Sony DVD/CD Player.

My upgrade plan is to add a CD Player & Sub-Woofer.

CD Player Options: Rega Appollo, Naim CD5i, CA Azur 840C, Cairn fog V2 (not easily available), Simaudio Moon Equinox , Sony dvp-ns999es, any good tubed CDP (All Pre-Owned)

Sub-Woofer Options: REL Strata III, REL Storm III

So I need your help for the following questions:

1. Which change will make more positive impact on the sound system....CDP or Sub ? ( I will go with the second upgrade few months down the lane ).

2. If CDP needs to be upgraded, what would you recommend between Naim, Rega, CA, Cairn Fog, sim and tubed cdps for my system (primaluna 2 and Arros) ? I like warm organic music with excellent vocals, instruments and strings with good BASS. Just want to remind again that I am using tube integrated (primaluna 2) for getting the warm preso and planning to add REL Sub for the quality BASS.

3. Since I already have a tube integrated in the line, should I be looking for a CDP that delivers excellent PRaT and Bass like Nait CD5i / Simaudio (or) more warm presentation of Rega (or) more warmer tubed cd players?

4. I read great reviews of 840C and it was being compared to Naim CD5i. I would like to know the system harmony of CA 840C with Primaluna 2 and Totem Arros for my music ?

5. Since I would like to add more Quality BASS (using REL), which of these CDPs make more sense ?

6. How does a modestly priced Sony dvp-ns999es (pre-owned) compete with the likes of Naim, Sim, Rega, etc ?

I will be eagerly awaiting your feedback for improving my 2 channel system. Thanking you all in advance

Mike