Belles Virtuoso or PrimaLuna DiaLogue Premium HP

My amp is also autobias and very revealing of tube changes, driver, power, and rectifier tubes all. Rolling tubes is certainly one of the fun parts of the hobby. And regarding Belles yes widely praised gear for sure and I am sure the new amp will be a good one but, no ones actually heard it yet. I'm not saying that's good or bad just a ton of hype for an unreleased unheard product. So the choice is yours but you certainly have some good choices before you.

I’ve considered the option of adding a buffer between source and amp. Seems like a viable option. 
Ive always lusted after ‘the tube sound’, and am finally at a point where my kids are old enough, and I’m ready for a change. My Adcom gear will be going to my shop with a pair of old Kef Q300 I have laying around. I am really leaning towards the PL. I’ve looked at other offerings from Line Magnetic(219ia), Atmos-Phere, Ayon, etc. The PL just strikes me as an easy way into tubes. 

I've been doing this for a long time and have dabbled in SOTA stuff as well as some moderately high end stuff, solid state and tubes. I have now settled into two PL Dialogue integrateds, the One and the Two. Two systems. They are about 4 to 5 years old and have not required any service. They are infinitely tunable by selection of power and small tubes and having that ability will keep you occupied for a while. :-). That said I must admit I have not heard the latest PL's. I'm happy with what I've got.

For the people that own PL stuff, How big is the difference in SQ going from the PL Dialogue premium HP integrated, to the Dialogue preamp, and the Dialogue HP amp? I’m worried that the preamp section of the integrated isn’t going to be as ‘revealing ‘. I’m just speculating, as I have no experience comparing the 2.

Since you're just speculating (:-) so will I. I've never compared them. It is likely that the pre/amp combo will have at least slightly better resolution, or at least presentation of detail, but unless you have very high quality speakers which have been set up to optimize their sound/room interface, it is more likely that you will not detect the difference. You will also optimize your ability to change the tone because you will have more tubes to play with (and IC's, etc). I subscribe to the KISS philosophy and maintain a decent level of sanity. :-)  BTW I think I read about some comments in one of the mag's (Stereophile (?) about the Amp/Pre combo which indicated the combo might not be optimum but I never actually researched it further. You might.