I am indeed viewing the print in too dim of lighting, and that is great first suggestion. I will set up a standard viewing environment. How many lux do people usually use when viewing prints that they make for other people?
I believe that my working space has gamma 2.2, I scan images in epson scan 16bit grayscale, which seems to output untagged files when I look at them in Photoshop. I usually do all of my editing in lightroom (with minor exceptions), and export for QTR in 16 bits/component in Adobe RGB (1998), which I believe has gamma 2.2. I do not see ICC profiles for QTR in colorspaces when exporting, so it seems like these icc profiles are not installed per default in windows when installing QTR. I will see if I can find them and add them manually. Would your advice be to use these as the output color space instead of a normal 2.2 space?
I have not generated output for printing for photoshop, but if I do it sounds like the right thing to do is to convert the untagged files to gray gamma 2.2 (rather than assign) before writing the tiff, correct?
My monitor is not super fancy but it is definitely capable and designed for high quality viewing (it is a Dell ultrasharp U2413, with 99% coverage of Adobe RGB and 100% of sRGB), so that would not be my first suspect. It has been profiled with a Colormunki Display which is by no means the fanciest of devices but I would imagine it does a decent job.
One thing that I am definitely not doing is to soft proof with QTR profiles; I had no idea these existed. I assume they are generic profiles that roughly match what QTR will output? Where can I get more information about this? I am indeed printing on a PC from QTR, so I will soft proof with "preserve RGB numbers".