beginner seperate system

If you amp/speaker combination satisfies and you want to add tubes to the system then I suggest you purchase a tube amp that is compatible with your amps. I believe most any 2-channel preamp would be superior to usig a AVR as a pre. 

I currently run a Jolida tube preamp into a SS amp. Like you wanted tubes, just not a tube amplifier.  

Good luck in your search!

I looked at purchasing the Focal Aria 948's and I kept asking the dealer, "WHERE'S THE BASS."  I am sure your subwoofers were able to give the added bass extension they needed.  I did like the tweeters and mid drivers, as they were very musical.  Surprised you have not looked into buying a pair of the REL T/9i's or the REL S3's.  They work differently than the Rythmic and are more discrete to build a larger sound stage.

I ended up with a pair of the Paradigm Prestige 85F's and I should have held off and purchased a true 3 way speaker.  I am not sure why Paradigm designed these as a 2 1/2 way.  However, the Vienna Acoustic Mozart's are also a 2 1/2 way.  They have a very solid bass extension.  I believe they get down to 24 Hz.  

I went to the Rocky Mountain Audio Fest in October and listened to a pair of SALK Song3 Encore's, priced at $6,000 and they sounded better than a pair of $60,000 speakers I listened to.  Jim Salk sells direct and as a result, he can afford to buy the best drivers available to deliver incredible sound quality.  They get down to 24 Hz and there would be no need to add a subwoofer.

Not sure what the attraction is for a tube amp.  I know they sound warm, but can they deliver the detail like the Parasound Halo Integrated Amp?  I am a huge fan for Parasound,  I am also very satisfied with the ARCAM AVR550  I purchased.  However, the ARCAM AVR859, at a price of $6,000 is really incredible, as it sounded much better than the MacIntosh I listened to side by side.  Their G technology provides pure A for the first 50 watts.  The nice thing about ARCAM is you can listen to both 2 channel and surround for home theater applications in the same room.

Quicksilver. Good reasonable tube amps. Mid monos by Quicksilver made the top 5 list for a respected audio expert with no skin in the game. Don't do Chinese, I did and it was terrible.

I own Quicksilver Mid Monos too.  Great amps !!!   They just came out with a pair of new 60 watt monos that look awesome.  Auto bias scheme that adjusts with respect to output power.    I think QS represents one of the best values anywhere in audio.   Stuff is built like a tank and has been super reliable.  

If I were you, I would either PM or call Johnny Rutan (Audioconnection). He will set you up with the best you can get for the money- with no pressure or sales pitch.
He knows home stereo like the back of his hand.
I only post this because you are going to get lots of recommendations, and Johnny knows just about all the gear out there and can give you some great advice as to how to proceed.
HTH
B