Ed, I don't use the promist very much because it's a little too foggy for me. The one I use the most for closeups is the Schneider Classic Soft 1/2. It is very subtle but quite effective in my opinion.
Here is the Classic Soft:

Yes, that's lovely. Much nicer than the BPM

Tiffen UltraCons would be a little like lifting the Master Video Black slightly while also engaging Black Stretch (Black Gamma) -- not sure if you could forgoe the filter and do that only with the menu settings... but in theory, the advantage to using the filter would be that it wouldn't contribute to an increase in noise.

I suspect the best thing would be to test a combination of these techniques.

In addition to what the UltraCons do, the Schneider DigiCons also suppress some bright highlight exposure, probably with some sort of black specks in the filter. Again, compared to using the knee function or simply underexposing slightly to hold more highlight detail, probably you'd want to test a combination of approaches along with the filter.

You can see a test of the filters here:
http://www.cinematography.net/digicon-test.htm

Generally it's always easier in post to slightly increase contrast than to reduce it, because it's always easier to throw away information than recover it, especially if it was never captured. But there are limits when dealing with compressed images.