-
As per my comment up thread I favour a stem and top tube that are parallel. The combination of -10 stem works best with the overall frame geo I think. It can also be parallel using a -7 stem and a shorter seat tube but I don't like it as much visually.
With this design I technically can still use a -7 stem, it just means the top tube and stem won't be parallel. I am not planning on running the stem fully slammed anyway; the design allows for a small amount of spacers for flexibility changes, so this can also accommodate different stems without altering the overall fit triangle
How come you want/need a -10°? Doesn't it make more sense to design it so you have access to the most common sizes available?