I think the problem here is all the digital guys that have 'lowered' the market standard. What I mean is many, many digital photographers give away images on CD - all of them and all hi res 'cause they want a portfolio so badly. So here you are competing the likes of the digital snappers.
I am in the same boat. But, I stick to my guns. When I shoot TFP, I flat out tell the models that:
1. I shoot film
2. I don't shoot a bajillion shots, just one roll per look - that 12 pics on MF
3. I always have an MUA minimum and usually I have a stylist
4. She only gets a few (at most 2 shots per roll - usually only one shot per roll and maybe another couple from the entire shoot - this usually ends up about 6 at most and averages 3) hi-res pics for her portfolio and web quality pics for whatever she want
5. She signs a limited model release
But it's tough because of your digital competition and the lowering professional standards out there. Stick to your guns. Shoot quality work and the work will come. Many models are starting to want more than just 'agency' pics - they want artistic pics and pics they like in their portfolio.