I think many hear have tried without success to give you sound advice, but you do not take it.
I will have one more go.
First you seem far too swayed by subjective opinion. This leads to your next problem that you change systems and gear like shirts.
This is costly and defeats your aim of putting together a superior system.
For instance, your speakers are very middle of the road at best. The speakers are dominant over everything else in the sound and quality of your system.
For all the money you have blown so far you could now own much better speakers than you have.
My next point may be a strange one. The world of audio has moved on. Unless you are really into exotics 2 channel preamps are no longer large volume. In this situation you are likely to build in unreliability with that Parasound. An unreliable unit is no good, whatever other attributes it may have. Not only that you could have discerned that its design is very old fashioned. This is a problem as components like analog volume controls are not of the quality they were years ago.
If you really wanted a system like you constructed good vintage equipment would have been a much better bet. I know it is 2.1, but you can easily add outboard bass management to any two channel preamp. I have done that to my system downstairs.
Now as to AV preamps they won't affect your sound I don't believe. Pre amps have a fidelity that usually outclasses everything else in the chain.
I own two Marantz pre pros.
It looks for your purposes you do not need all the bells and whistles on the newer ones.
I'm still using my older Marantz AV 8003 and have no desire to put it on the replacement list.
I have bench tested it and it has no defects that would be in any way audible.
You might want to look for one on eBay. They generally go now for around $750.
You need to think a little harder about your purchases and look much harder at reliability.
With the speakers on your equipment list you will not tell the difference sonically, so go for build quality and reliability.
