Also check out the military soft shell pants made by Patagonia- a very nice weight fabric (light to mid weight) that stretches some, breathes well, has a very good DWR finish and are extremely durable (they are military pants after all :)). They have built in suspenders that really work.
These have been my go to mountain pants for the fall- if it's warmer I just wear a thin pair of of merino boxers, cooler a thin lower base layer, cold a thicker lower base layer.
Not cheap ( but not terribly expensive either), but good mountain pants aren't going to be cheap.
Worth a look.
