"I guess ultimately the fix is to set the gain on my mixer to a much lower level and simply read the digital metering. I don't really feel satisfied with that though for some reason,"
You have my sympathy Chris! "We" did try to rationalize things many years ago (had bumber stickers "600 Ohms is dead!") but around a century later dBu (was dBm) is still with us and the 0.775V reference comes from the telephone industry when, AFAIK, there were no amplifiers even!
There IS a downside to working at -10dBV, the signal exchange system, cables, are more prone to picking up interference but for the short runs in domestic surroundings this is rarely a problem*.
The signal levels inside and going to and from gear is related to and determined by the DC supply voltages inside said gear. "Pro" kit will have effectively 36volt supplies (tho' 34V is better for reliability) whereas your domestics will be 30V or even as low as 24V.
Running higher internal supplies is more expensive. Transformers, capacitors all cost more and the gear will run warmer and maybe need to be bigger and metal costs!
Manufacturers for the most part do not help us with specifications. What we REALLY need to know is what input voltage (in millivolts/dB) produces -18dBFS in the software or any other dBFS level we can get a handle on.
But if just backing off the mixer output bugs you Chris and you intend to keep on with this recording game. Learn to Solder! You will find as you progress that mic cables ALWAYS fail at 16:30 of a wet Sunday and there is no shop open! Then you can and will want to experiment with connecting gear or even just need to connect something with a non-standard connector, having some electronics smarts can be of enormous use.
I am not suggesting you build a synth or something! No, just passive stuff (for now but the PP3 is always with us!) The attenuator box I referred to earlier is very simple, will post a set of drawings if you like?
*Tis a little known fact, a BALANCED line input will always be considerably noisier (hiss) than a simple unbalanced one unless VERY carefully and expensively made!
Dave.