Moose,
I'd say our hair is very similar. Been on finasteride for about a year. I think my hair initially got thinner on finasteride, but it has stayed consistent so i guess i'll accept a slight thinning so long as it stays the same for the next few years.
Though, I have to say that I think receeding is better than diffuse thinning because you can go a lot longer before it's noticeable. I have a friend who started receeding about seven years ago, but the rest of his hair is so thick, and he wears his hair with a part so the hair curves down his forehead, and you would never even think he's losing his hair. Even if it got to a point that it bothered him, with all that thick hair he could easily get a transplant. Not always an option for diffusers.
On a positive note, i would think diffusers would respond better to finasteride. I don't know if that is entirely true or not.