do you have a sperate audio and HT system?

I used to have a single integrated system like the one you describe. When my financial circumstances changed for the better, I decided to go in a slightly different direction. I continued to use Krell solid state electronics and Thiel speakers for my HT rig. But I went with Audio Research vacuum tube electronics and Magneplanar speakers for music. They are in separate rooms. Each has its own strengths and weaknesses, but I am very happy with both.

Most recently, I added a Pioneer PV 47ai to the HT rig for multichannel SACD/DVD Audio.

I'm integrated just like yours. My stereo preamp has a SSP loop which I have my Denon receiver running through. I'm fine with it for the last year or so. Much better than when I tried to go music through a high end SSP (Proceed). The only limitations are that many preamps still don't have SSP loops, so it limits your preamp choices. However, I don't have any plans for changing my setup in the near future, unless I roll into a big chunk of change like Kinsekd.
Here is my system:
http://db.audioasylum.com/cgi/m.pl?forum=systems&n=1343&highlight=justlisten2&r=&session=

I am an avid 2 channel advocate, as well as a HT multi channel junkie. I DO NOT LIKE to compromise teh integrity of my sonics, at ANY TIME!!! If I can't have quality sound, from any of the systems I may set up, I would rather not at all.
I've come to the place in my life that I've become addicted to SPECIAL sound quality, as well as video quality! I would MUCH RATHER build a dedicated 2 channel system,with integrated pre/pro for the movies, and do what you are doing with the "processor through-put" on your preamp, and just switch for different sources, then to get 5 channels of MEDIOCRE TO POOR OVERALL SOUND!...ANY TIME!!
Actually, the way you are doing it is the way to do an "integrated" 2 ch/HT system really. Even just doing 2 speakers with a good subwoofer integrated is excellent overall sonically if you do it right! You still need to run your mains as "small" usually from the processor for movies, and let powered sub (unless your speakers have powered subs built in) handle the demanding bass from movies(and rock ideally).! You can get away with a good amp and some full range speakers run, well, full range for most music dubties(although more dynamic the other way), but not for movies! It never sounds as dynamic and powerful. Also, a digital pre/pro is A MUST for movies..which you're doing.
So, I think you're doing it right largely.
I think there's WAY TOO MANY people out there who don't have quality ALL AROUND, and are just getting by with COMPROMISED sonics from A LOT OF speakers...but that's ok.
For me however, If I can't do quality from EVERY POST, I'll skip thanks.
Another thing, receivers are largely done for me...they don't have the refinement, dynamics, noise floor, or ch/separation and strenght of detail to sustain me for HT! Separates IS THE WAY to go.(all you RECEIVER JUNKIES TAKE NOTE!...separates wax receivers in every way!!!..end of story.)
Really, probably 90% or more of the people have an "ALL IN ONE" system. So, you gotta make do with what you got. All the audio reviewers have separate systems. And to MAXIMIZE both of them, you largely usually do have to do 2 systems almost these days. But, if you know what you're doing(most don't), you can do it right with one system. But to do a top notch job, you REALLY gottab be up on your game!...and that takes time, experience, and dedication...things most don't have.
At any rate, it's all good...somes just "gooder" than others!
Have fun