I'm looking at using the new displacement map functionality for rendering wool pile or bristle pile. Right now we're overlaying imagery on the top and sides of our wool pile to give the appearance of bristles (see below), but it would be nice in close-up shots to have a more realistic appearance of wool pile. I'm looking at the displacement map to basically generate bristles for rendering. I know I won't get it to look like actual hair, but I'm hoping it won't look as flat and straight as it does now. 

Our models for wool pile consist of a lot of flat surfaces and there simply aren't enough mesh points to properly displace the surface. Is there a way to increase the mesh complexity on a model? (preferably of a selected surface). I've seen some decimation tools, but I haven't seen a way to increase complexity. 

Currently rendered look (3 separate appearances per wool pile piece):

Actual look:

Thank you.