While not bike-specific, I've found that Kuhl makes slimmer, technical pants with ventilation that seems durable and are presentable at work. In Texas I can only commute in pants in the middle of winter though. I have to wear shorts most of the year and change at work. Vuori makes some good pants too, again, not bike-specific, but they work well. A little pricey though.
For bike-oriented brands, check out Chrome and Swrve. There's always discount codes for them.