how important is linestage preamp with vinyls only

The linestage provides two functions, if you are using an outboard phono stage. It adds gain. If the output of your phono stage is inadequate to drive your amplifier, that gain is needed. And it adds an attenuator in the signal path and possibly bass/treble/balance controls if you want to use such. Both the gain function and the control functions can also color the sound, for good or ill. If your phono stage has a robust output with the cartridge that is driving it, and if it has a volume control, there is no need for a formal linestage at all.

(There is a third issue with impedance matching; the phono stage has to have a low enough output impedance to drive the cables between it and the amplifier inputs, in order to do away with the linestage.)

If your question is whether or not to switch from a full function preamp (meaning a preamp with built-in phono) to separate phono and linestages, I would say that it is impossible to say, since only you can determine what pleases you most. But separate boxes will cost more, require another interconnect pair, etc. Rollling tubes may help, but what are you trying to achieve? Changing capacitors in the signal path would likely help even more than rolling 12AX7s in the CJ.

If you plan to use stand-alone phonostage with volume control like EAR834, it'll keep you with tube business and you won't need preamp.

Thank you everybody.
To Thorman – yes, you are exactly right about trying different tubes. The thing is I was almost at the point to buy some tubes (good ones) from Brent Jesse, $300-500 range per matched pair. I looked at other places as well. Should I mention that I started from ground zero exactly a year ago. So at the time I just needed to start somewhere and I bought the PV12 (this has 12AX7, 5751 and 12AU7) which didn't fail me yet.
But while speaking with Brent it crossed my mind that not all pre-amps (and I intended to stay within CJ for time being, but even with those) have the same tubes – some have 6922, some 6H30P and so forth. This and the fact that good tubes are costly made me consider the upgrade first, as well as a minor fact that the PV-12 doesn’t have the remote.
And certainly, regarding the question on what I am looking for – it is hard for me to realize the deficiency of the sound until I hear something else. I am quite happy with the PV12 sound as it is now. I should add – provided the record quality is sufficient/high enough. On some records violins are too harsh, on some bass is not too expressive, but since I have a few records which sound very good I assigned the above week points to the record rather then to the device. But on the other hand I thought I should rather go a little higher, get myself a (as they say) better (read – more pricey) CJ device, run it at my place with all the arms and cartridges that I have and then decide. But you are right – one needs money for the vinyl J
To Newbee – on the cartridges side – I have a few, I have not decided though which one (or ones) I will keep. I have Grado Reference (Old Stock), Grado Amber the Tribute, Ortofon Windfeld, Acutex M320 and VDH Colibri LWG. “Only” 2 arms so far – the Rega 300 that came with the used TT (Oracle Paris, old model) and Sumiko MDC800. I am planning to get a light weight (may be some used SME) for my high compliance Colibri, as well I am considering a used RS-212D for Windfeld. Yes, I like music more than HIFI but I don’t mind having some fun with different setups as long as I don’t take the next mortgage.
Speaking about the tone – I would say balancing the details and the ‘warmth’ I will go for the latter maintaining enough details as much as I can.
To Lewm – good point about the controls on the phono stage, I didn’t think about it that way! I was missing tone controls on the pre-amp initially when I started but now I don’t think I miss that part too much. I also spoke with Ed from CJ about changing the capacitors in the PV12 but it doesn’t look like they do such an upgrade in PV12. They do that on the PR16 amp (and EV1 phone stage) though. And this was another reason for my question as well.
But overall it looks like I have more defined plan now thanks to you folks.
Regards

Dear Avs9, You have some top quality cartridges, a really good selection. Pardon my saying so, but the cartridges exceed the capabilities of your two tonearms. A tonearm upgrade might produce more results for you than tube rolling, not to mention that you should also check out your tt to be certain the belt is not stretched out, etc, and that it is running at correct speed even when under load while playing music. Those are easy things to do.

I don't want to take business away from anyone, but the price you quote for matched tubes is, shall we say, high. Remember that matched tubes can age at different rates such that eventually they are no longer matched, and in all but balanced circuits, I think matching is over-rated. So long as the tube is not noisy and as long as both halves of these dual triodes are in good condition, I would just use singlets. Lots of tube vendors will test for this standard.

I find it odd that CJ says they will not upgrade the coupling caps in your unit but they do so for other products. Any good local tech can do it for you, if CJ won't. Try some teflon output caps; you will be amazed. Finally, be aware, if you are not already, that you cannot just plug any old 9-pin miniature tube into any old 9-pin socket. To use 6DJ8, 6922, 6H30, etc, in your preamp would require some major re-design of the circuit. But if 12AU7 is begin used as a cathode-follower at the output, you might try an ECC99 there or any of several 12AU7 direct subs.

Dear Lewm,
I got it wrong from CJ I am afraid – just spoke with Ed from CJ, they CAN do the teflon ones on PV12, the price I guess is not a secret it is $1200. I am not sure if I can find a cheaper option here. The teflon upgrade on the PR16 is actually much more! So I may consider staying with PV12 after all.
Yes, thanks for pointing out my arms deficiency. The upgrade was actually planned, still working on it. Now if you can make another step – how does RS-212D sound (used, mint for $1450) for Windfeld and used SME 3009 type for Colibri? The Colibri Light Weight is a demanding baby, with only 5 grams weight it asks for the lightweight arm not above 14-16 gr effective mass. The thing is I can not bring myself to buy what is being a little far from the classical (IMHO) type like SME IV or SME V or linear tonearm. I am more into classical style like Ortofon, Origin Live, earlier SMEs etc… I guess the Ortofon applies some fees with the brand name, not sure how wrong it would be to assume that the Ortofon arm will suite the Ortofon Windfeld better, they seem to fit based on the compliance factor.
For the tubes price I checked a few sites mentioned on this forum, the best ones like Mazda silver plate triple mica is $425 per pair, 12AX7 Telefunken smoothplate, diamond mark 1960s, $230.00 per pair. So yes, you are correct - there are options, staying with PV12 I probably don’t have to go high, like you said with cartridges – the PV12 (and my CJ MV60SE later in the chain and not above average speakers, I used Audes from Estonia) would probably limit the benefits of the most costly tubes. I need to do more leggwork here I guess.
Much thanks