My monitor at 90 cdm2 is as low as I care to go. It's a NEC 2490 with Spectraview. When I calibrate below 90, the Spectraview software tells me my Delta-E is going south. Forgot to mention in previous post that my "pool table" print viewing light measures about 100 using the camera trick. So 90 monitor and 100 print viewing is as close as I can get.
Yes, it could be better. But remember that the whole business of profiling is an inexact endeavor. Carefully edited images end up displayed on a wide range of monitors. Cell phones, laptops, tablets, desktops... few, if any are properly adjusted. Prints end up on walls or desks in homes and offices, under all kinds of lighting conditions, mostly poor.
None of my work ends up on gallery walls, under special lighting, selling for hundreds or thousands of dollars. If it was, I'd try harder. Only when I'm making a very special print, like for a competition, do I really worry about it. I only do that once a year and I do hard proofing. I make a print, put it on display, and study it for 2 or 3 days. Sometimes I decide to re-edit and re-print, but not often.