Digital BW, The Print

Hi all,
    I'm a new comer to digital black and white, so I hope this isn't 
a ridiculus question.
    I'm using Jim Nevins curves with FS MIS inks in an 1160.  I 
continue to have problems with dark images.  After the curve is 
applied the images print very dark.  If I lighten the image with 
brightness, contrast or a tonality adjustment, it results in a flat 
image with blending of the grays, little contrast and a very digital 
look.
    I did a gray scale stepwedge and created my own curve which was 
not perfect, but close.  This brought back contrast and more detail 
to my images, but they still print very dark.
    Do I need to go all the way back to the camera and increase my 
exposure or is there a nice way to lighten these images up and keep 
detail and contrast? 
                   Thanks all,
                           Scott Michener