I started as a black & white photographer in Lightroom, scanning negatives to TIFF's and then adjusting and printing.
After also bringing in RAW files, I believe there is no one preset that will provide any good conversion to b&w. I say this because of the step process needed to properly set the contrast and range for a b&w image.
Adobe did a good job putting the development panels in order. I suggest to you that any conversion in b&w start first with the exposure settings.
Getting a reasonably good histogram is an important place to start. After that is achieved, then fine tuning with the image curve will help separate some tones further or compress them if need be.
Finally, if there is more tonal work based on colors in the photos, I would use some sort of HSL slider combinations to emulate colored filters. I created some based on some work done here by Chris Brandon. You can get them here:
http://outdoorimages.blogspot.com/2''8/'5/lightroom-presets-available-black-white.html
I give you all this discourse, because any generic preset will tend to adjust all of these items. While the end result is important, in my experience the proper order is more important. Small adjustments along the way may change how you make further adjustments. Even starting with some dramatic preset that plays with the tonal curve will affect how you might make exposure changes - and this may not be what you want.
NOW, if you have a shoot with 2' or so images, correcting one and then synching the settings can be a very reasonable and easy way to adjust all the images to the correct settings - it stands to reason that the same subject in the same light would require roughtly the same settings. The issue is, this would be a onetime use setting, not applicable for a different subject in different light.
Hope this helps. I'd be interested in what other's think.