there is a lot of bad advice on this forum and every audio forum because most of the members get their info from people trying to sell them bigger and more expensive amps. There are dealers who are members here to throw fuel on the fire.
I had Martin Logans CLS and what I liked most about them was the tremendous midrange that sounded excellent at low volume. of course they lacked bass but ML fixed that with the hybrid and your 11A sould be spectacular at low volume.
I often say that if your system has to be turned up to sound good, then your system sucks. Not attacking your system at all but I commend you for wanting to achieve what most people here think doesn’t exist.
First, lets look at your source. the Qutest is nice, probably your best bet in that price range. I have the DAVE. I upgraded DAVE to a Lampizator GG3 but right now I am back to DAVE as my Lampizator isn’t playing nicely with the Amp. A used chord DAVE is an awesome buy right now as they are getting old but still sound excellent. Between the DAC and the AMP, I have a Transformer Volume Control by Akustika Eterna (disclosure, I have an interest in that company). Using the TVC makes any system sound "bigger" and "fuller" at low volume. It it is a bit spendy.
Streamer--I have a grimm which is a higher price range but you get the least bang for the buck upgrading your streamer. So I would focus elsewhere.
Now to the meat of the system. I discussed the source first because GIGO, you have to have a good source. But then if your amp isn’t great, you’ll lose all the good work you are doing at the front end. At your listening levels, you’re listening to 1 watt or less. But you have a 300W amp. I’ve yet to hear a 300W amp that sounds great at 1/2 watt. I’ve often wondered if you can get by with a 6 wpc 300b amp on the new MLs since the bass is provided by the onboard amp. Probably not. But I did try my ML CLSs with a 30 wpc push pull tube amp that sounded great. That was a decware ZMA. If you don’t want tubes, there are many lower power ss amps that focus on giving you a great first watt. but as they say, if the first watt sucks, the next 299 won’t help. Focus on the first watt.
So in conclusion, I’d focus on the amp first and then the DAC. I have a friend who uses the Qutest in a very excellent system that sounds great at low volumes.
Jerry
PS you can probably lose the preamp. Preamps aren’t necessary in most cases but again, dealers always want to sell more gear and owners always want to stand behind their buying decisions. they just add another level of processing that takes away from the great sound, espcecially at low levels. easy to try--plug your DAC into your amp and see how it sounds. I don't think the Qutest has volume control (DAVE does) but you can use Roon volume control is pretty good if you use Roon. of couse I recommnd the TVC mentioned above but it is another expense.