You will be able to give yourself a “crunchier” black and white effect with the YUV curves in ColorFX.
Flatten U&V so that they lie completely horizontally and directly through the centre. Don’t worry, you’ll be able to see if they’re off centre pretty easily.
Then use a gentle (or not-so-gentle) S-curve in the Y, and you’ve got yourself a much nicer, custom B&W filter, which you can save to use again and again.
All the best,
Ben