First World Problem in need of Solution

My problem is that I would like to upgrade my system to a 5.1 system however I am worried about matching sound to what I currently have. 

Gear
AMPs Luxman M-900u run as mono blocks
PreAmp Luxman C-900u
Subs - SVS SB4000 - these are run via XLR from PreAmp to Sub so listening is speaker A+B
DAC PS Audio Directstream 
Fronts Focal Sopra N 3 
Rears Focal Sopra N 1 
Center Focal Sopra center

Possible Solutions 
1)
Buy a HT Processor and run rear and center out of it and use the HT Passthru on the Luxman Preamp. 
Concern
Sound is going to sound different from the rears and center than the front left and right
Thoughts: This seems like the best solution because my 2 channel listening will not be compromised

2) 
Buy a HT Processor and run rears and sub out of it. Convert the mono blocks into a normal 2 channel amp and run the center speaker into a dedicated amp. Or I could run front and rears off of the mono blocks and the center off of the the HT Processor 
Concern Potentially losing the subs in 2 channel listening. Center sounding off. The N. 3 only have one amp drive them
Thoughts: This just seems like a nightmare

3)
Sell all my gear and replace with another brand that also has HT lineup so I could accomplish all of my goals
Concern: 2 Channel Listening is going to be compromised
Thoughts: Maybe the best option? 

4) 
Scrap the 5.2 and go to a 3.1 setup. Run an optical out from the TV to the DAC. Run the monoblocks as regular amps. 
Concern: 2 Channel listening compromised, NO BASS! Unless I could run them out of the DAC? Maybe
Thoughts: UUGGGGHHH

Can some of you who have more experience weigh in on which way you would go or which option seems "best to you".

Also any suggestions for HT processor would be helpful. 

Thanks  in advance 

G