Good Pants: topology and edge loops

aaráribel caađo

I've been making more clothes now that I can sim then instead of rigging them when I feel lazy. I'd like to establish a lightweight base mesh to use for modeling shirts and pants from, rather than starting with primatives, and I want the base meshes to have solid topology. However, I'm not sure about the best topology for pants. Right now, I have loops extending up the front about half way between the crotch and the waist, but they don't extend much above the crotch in the back. Is this a good practice, since legs mostly bend forwards? Or should I mirror my front loops to the back? 

The base mesh is all quads, and all have four quad cornrs except for the five-quad corners with the verts highlighted.